1//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements semantic analysis for expressions.
10//
11//===----------------------------------------------------------------------===//
12
13#include "TreeTransform.h"
14#include "clang/AST/ASTConsumer.h"
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ASTLambda.h"
17#include "clang/AST/ASTMutationListener.h"
18#include "clang/AST/CXXInheritance.h"
19#include "clang/AST/DeclObjC.h"
20#include "clang/AST/DeclTemplate.h"
21#include "clang/AST/EvaluatedExprVisitor.h"
22#include "clang/AST/Expr.h"
23#include "clang/AST/ExprCXX.h"
24#include "clang/AST/ExprObjC.h"
25#include "clang/AST/ExprOpenMP.h"
26#include "clang/AST/RecursiveASTVisitor.h"
27#include "clang/AST/TypeLoc.h"
28#include "clang/Basic/FixedPoint.h"
29#include "clang/Basic/PartialDiagnostic.h"
30#include "clang/Basic/SourceManager.h"
31#include "clang/Basic/TargetInfo.h"
32#include "clang/Lex/LiteralSupport.h"
33#include "clang/Lex/Preprocessor.h"
34#include "clang/Sema/AnalysisBasedWarnings.h"
35#include "clang/Sema/DeclSpec.h"
36#include "clang/Sema/DelayedDiagnostic.h"
37#include "clang/Sema/Designator.h"
38#include "clang/Sema/Initialization.h"
39#include "clang/Sema/Lookup.h"
40#include "clang/Sema/Overload.h"
41#include "clang/Sema/ParsedTemplate.h"
42#include "clang/Sema/Scope.h"
43#include "clang/Sema/ScopeInfo.h"
44#include "clang/Sema/SemaFixItUtils.h"
45#include "clang/Sema/SemaInternal.h"
46#include "clang/Sema/Template.h"
47#include "llvm/Support/ConvertUTF.h"
48using namespace clang;
49using namespace sema;
50
51/// Determine whether the use of this declaration is valid, without
52/// emitting diagnostics.
53bool Sema::CanUseDecl(NamedDecl *D, bool TreatUnavailableAsInvalid) {
54 // See if this is an auto-typed variable whose initializer we are parsing.
55 if (ParsingInitForAutoVars.count(D))
56 return false;
57
58 // See if this is a deleted function.
59 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
60 if (FD->isDeleted())
61 return false;
62
63 // If the function has a deduced return type, and we can't deduce it,
64 // then we can't use it either.
65 if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
66 DeduceReturnType(FD, SourceLocation(), /*Diagnose*/ false))
67 return false;
68
69 // See if this is an aligned allocation/deallocation function that is
70 // unavailable.
71 if (TreatUnavailableAsInvalid &&
72 isUnavailableAlignedAllocationFunction(*FD))
73 return false;
74 }
75
76 // See if this function is unavailable.
77 if (TreatUnavailableAsInvalid && D->getAvailability() == AR_Unavailable &&
78 cast<Decl>(CurContext)->getAvailability() != AR_Unavailable)
79 return false;
80
81 return true;
82}
83
84static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) {
85 // Warn if this is used but marked unused.
86 if (const auto *A = D->getAttr<UnusedAttr>()) {
87 // [[maybe_unused]] should not diagnose uses, but __attribute__((unused))
88 // should diagnose them.
89 if (A->getSemanticSpelling() != UnusedAttr::CXX11_maybe_unused &&
90 A->getSemanticSpelling() != UnusedAttr::C2x_maybe_unused) {
91 const Decl *DC = cast_or_null<Decl>(S.getCurObjCLexicalContext());
92 if (DC && !DC->hasAttr<UnusedAttr>())
93 S.Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName();
94 }
95 }
96}
97
98/// Emit a note explaining that this function is deleted.
99void Sema::NoteDeletedFunction(FunctionDecl *Decl) {
100 assert(Decl->isDeleted());
101
102 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl);
103
104 if (Method && Method->isDeleted() && Method->isDefaulted()) {
105 // If the method was explicitly defaulted, point at that declaration.
106 if (!Method->isImplicit())
107 Diag(Decl->getLocation(), diag::note_implicitly_deleted);
108
109 // Try to diagnose why this special member function was implicitly
110 // deleted. This might fail, if that reason no longer applies.
111 CXXSpecialMember CSM = getSpecialMember(Method);
112 if (CSM != CXXInvalid)
113 ShouldDeleteSpecialMember(Method, CSM, nullptr, /*Diagnose=*/true);
114
115 return;
116 }
117
118 auto *Ctor = dyn_cast<CXXConstructorDecl>(Decl);
119 if (Ctor && Ctor->isInheritingConstructor())
120 return NoteDeletedInheritingConstructor(Ctor);
121
122 Diag(Decl->getLocation(), diag::note_availability_specified_here)
123 << Decl << 1;
124}
125
126/// Determine whether a FunctionDecl was ever declared with an
127/// explicit storage class.
128static bool hasAnyExplicitStorageClass(const FunctionDecl *D) {
129 for (auto I : D->redecls()) {
130 if (I->getStorageClass() != SC_None)
131 return true;
132 }
133 return false;
134}
135
136/// Check whether we're in an extern inline function and referring to a
137/// variable or function with internal linkage (C11 6.7.4p3).
138///
139/// This is only a warning because we used to silently accept this code, but
140/// in many cases it will not behave correctly. This is not enabled in C++ mode
141/// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6)
142/// and so while there may still be user mistakes, most of the time we can't
143/// prove that there are errors.
144static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S,
145 const NamedDecl *D,
146 SourceLocation Loc) {
147 // This is disabled under C++; there are too many ways for this to fire in
148 // contexts where the warning is a false positive, or where it is technically
149 // correct but benign.
150 if (S.getLangOpts().CPlusPlus)
151 return;
152
153 // Check if this is an inlined function or method.
154 FunctionDecl *Current = S.getCurFunctionDecl();
155 if (!Current)
156 return;
157 if (!Current->isInlined())
158 return;
159 if (!Current->isExternallyVisible())
160 return;
161
162 // Check if the decl has internal linkage.
163 if (D->getFormalLinkage() != InternalLinkage)
164 return;
165
166 // Downgrade from ExtWarn to Extension if
167 // (1) the supposedly external inline function is in the main file,
168 // and probably won't be included anywhere else.
169 // (2) the thing we're referencing is a pure function.
170 // (3) the thing we're referencing is another inline function.
171 // This last can give us false negatives, but it's better than warning on
172 // wrappers for simple C library functions.
173 const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(D);
174 bool DowngradeWarning = S.getSourceManager().isInMainFile(Loc);
175 if (!DowngradeWarning && UsedFn)
176 DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>();
177
178 S.Diag(Loc, DowngradeWarning ? diag::ext_internal_in_extern_inline_quiet
179 : diag::ext_internal_in_extern_inline)
180 << /*IsVar=*/!UsedFn << D;
181
182 S.MaybeSuggestAddingStaticToDecl(Current);
183
184 S.Diag(D->getCanonicalDecl()->getLocation(), diag::note_entity_declared_at)
185 << D;
186}
187
188void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) {
189 const FunctionDecl *First = Cur->getFirstDecl();
190
191 // Suggest "static" on the function, if possible.
192 if (!hasAnyExplicitStorageClass(First)) {
193 SourceLocation DeclBegin = First->getSourceRange().getBegin();
194 Diag(DeclBegin, diag::note_convert_inline_to_static)
195 << Cur << FixItHint::CreateInsertion(DeclBegin, "static ");
196 }
197}
198
199/// Determine whether the use of this declaration is valid, and
200/// emit any corresponding diagnostics.
201///
202/// This routine diagnoses various problems with referencing
203/// declarations that can occur when using a declaration. For example,
204/// it might warn if a deprecated or unavailable declaration is being
205/// used, or produce an error (and return true) if a C++0x deleted
206/// function is being used.
207///
208/// \returns true if there was an error (this declaration cannot be
209/// referenced), false otherwise.
210///
211bool Sema::DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
212 const ObjCInterfaceDecl *UnknownObjCClass,
213 bool ObjCPropertyAccess,
214 bool AvoidPartialAvailabilityChecks,
215 ObjCInterfaceDecl *ClassReceiver) {
216 SourceLocation Loc = Locs.front();
217 if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) {
218 // If there were any diagnostics suppressed by template argument deduction,
219 // emit them now.
220 auto Pos = SuppressedDiagnostics.find(D->getCanonicalDecl());
221 if (Pos != SuppressedDiagnostics.end()) {
222 for (const PartialDiagnosticAt &Suppressed : Pos->second)
223 Diag(Suppressed.first, Suppressed.second);
224
225 // Clear out the list of suppressed diagnostics, so that we don't emit
226 // them again for this specialization. However, we don't obsolete this
227 // entry from the table, because we want to avoid ever emitting these
228 // diagnostics again.
229 Pos->second.clear();
230 }
231
232 // C++ [basic.start.main]p3:
233 // The function 'main' shall not be used within a program.
234 if (cast<FunctionDecl>(D)->isMain())
235 Diag(Loc, diag::ext_main_used);
236
237 diagnoseUnavailableAlignedAllocation(*cast<FunctionDecl>(D), Loc);
238 }
239
240 // See if this is an auto-typed variable whose initializer we are parsing.
241 if (ParsingInitForAutoVars.count(D)) {
242 if (isa<BindingDecl>(D)) {
243 Diag(Loc, diag::err_binding_cannot_appear_in_own_initializer)
244 << D->getDeclName();
245 } else {
246 Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer)
247 << D->getDeclName() << cast<VarDecl>(D)->getType();
248 }
249 return true;
250 }
251
252 // See if this is a deleted function.
253 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
254 if (FD->isDeleted()) {
255 auto *Ctor = dyn_cast<CXXConstructorDecl>(FD);
256 if (Ctor && Ctor->isInheritingConstructor())
257 Diag(Loc, diag::err_deleted_inherited_ctor_use)
258 << Ctor->getParent()
259 << Ctor->getInheritedConstructor().getConstructor()->getParent();
260 else
261 Diag(Loc, diag::err_deleted_function_use);
262 NoteDeletedFunction(FD);
263 return true;
264 }
265
266 // If the function has a deduced return type, and we can't deduce it,
267 // then we can't use it either.
268 if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
269 DeduceReturnType(FD, Loc))
270 return true;
271
272 if (getLangOpts().CUDA && !CheckCUDACall(Loc, FD))
273 return true;
274 }
275
276 if (auto *MD = dyn_cast<CXXMethodDecl>(D)) {
277 // Lambdas are only default-constructible or assignable in C++2a onwards.
278 if (MD->getParent()->isLambda() &&
279 ((isa<CXXConstructorDecl>(MD) &&
280 cast<CXXConstructorDecl>(MD)->isDefaultConstructor()) ||
281 MD->isCopyAssignmentOperator() || MD->isMoveAssignmentOperator())) {
282 Diag(Loc, diag::warn_cxx17_compat_lambda_def_ctor_assign)
283 << !isa<CXXConstructorDecl>(MD);
284 }
285 }
286
287 auto getReferencedObjCProp = [](const NamedDecl *D) ->
288 const ObjCPropertyDecl * {
289 if (const auto *MD = dyn_cast<ObjCMethodDecl>(D))
290 return MD->findPropertyDecl();
291 return nullptr;
292 };
293 if (const ObjCPropertyDecl *ObjCPDecl = getReferencedObjCProp(D)) {
294 if (diagnoseArgIndependentDiagnoseIfAttrs(ObjCPDecl, Loc))
295 return true;
296 } else if (diagnoseArgIndependentDiagnoseIfAttrs(D, Loc)) {
297 return true;
298 }
299
300 // [OpenMP 4.0], 2.15 declare reduction Directive, Restrictions
301 // Only the variables omp_in and omp_out are allowed in the combiner.
302 // Only the variables omp_priv and omp_orig are allowed in the
303 // initializer-clause.
304 auto *DRD = dyn_cast<OMPDeclareReductionDecl>(CurContext);
305 if (LangOpts.OpenMP && DRD && !CurContext->containsDecl(D) &&
306 isa<VarDecl>(D)) {
307 Diag(Loc, diag::err_omp_wrong_var_in_declare_reduction)
308 << getCurFunction()->HasOMPDeclareReductionCombiner;
309 Diag(D->getLocation(), diag::note_entity_declared_at) << D;
310 return true;
311 }
312
313 // [OpenMP 5.0], 2.19.7.3. declare mapper Directive, Restrictions
314 // List-items in map clauses on this construct may only refer to the declared
315 // variable var and entities that could be referenced by a procedure defined
316 // at the same location
317 auto *DMD = dyn_cast<OMPDeclareMapperDecl>(CurContext);
318 if (LangOpts.OpenMP && DMD && !CurContext->containsDecl(D) &&
319 isa<VarDecl>(D)) {
320 Diag(Loc, diag::err_omp_declare_mapper_wrong_var)
321 << DMD->getVarName().getAsString();
322 Diag(D->getLocation(), diag::note_entity_declared_at) << D;
323 return true;
324 }
325
326 DiagnoseAvailabilityOfDecl(D, Locs, UnknownObjCClass, ObjCPropertyAccess,
327 AvoidPartialAvailabilityChecks, ClassReceiver);
328
329 DiagnoseUnusedOfDecl(*this, D, Loc);
330
331 diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc);
332
333 return false;
334}
335
336/// DiagnoseSentinelCalls - This routine checks whether a call or
337/// message-send is to a declaration with the sentinel attribute, and
338/// if so, it checks that the requirements of the sentinel are
339/// satisfied.
340void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc,
341 ArrayRef<Expr *> Args) {
342 const SentinelAttr *attr = D->getAttr<SentinelAttr>();
343 if (!attr)
344 return;
345
346 // The number of formal parameters of the declaration.
347 unsigned numFormalParams;
348
349 // The kind of declaration. This is also an index into a %select in
350 // the diagnostic.
351 enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType;
352
353 if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
354 numFormalParams = MD->param_size();
355 calleeType = CT_Method;
356 } else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
357 numFormalParams = FD->param_size();
358 calleeType = CT_Function;
359 } else if (isa<VarDecl>(D)) {
360 QualType type = cast<ValueDecl>(D)->getType();
361 const FunctionType *fn = nullptr;
362 if (const PointerType *ptr = type->getAs<PointerType>()) {
363 fn = ptr->getPointeeType()->getAs<FunctionType>();
364 if (!fn) return;
365 calleeType = CT_Function;
366 } else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) {
367 fn = ptr->getPointeeType()->castAs<FunctionType>();
368 calleeType = CT_Block;
369 } else {
370 return;
371 }
372
373 if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) {
374 numFormalParams = proto->getNumParams();
375 } else {
376 numFormalParams = 0;
377 }
378 } else {
379 return;
380 }
381
382 // "nullPos" is the number of formal parameters at the end which
383 // effectively count as part of the variadic arguments. This is
384 // useful if you would prefer to not have *any* formal parameters,
385 // but the language forces you to have at least one.
386 unsigned nullPos = attr->getNullPos();
387 assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel");
388 numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos);
389
390 // The number of arguments which should follow the sentinel.
391 unsigned numArgsAfterSentinel = attr->getSentinel();
392
393 // If there aren't enough arguments for all the formal parameters,
394 // the sentinel, and the args after the sentinel, complain.
395 if (Args.size() < numFormalParams + numArgsAfterSentinel + 1) {
396 Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName();
397 Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
398 return;
399 }
400
401 // Otherwise, find the sentinel expression.
402 Expr *sentinelExpr = Args[Args.size() - numArgsAfterSentinel - 1];
403 if (!sentinelExpr) return;
404 if (sentinelExpr->isValueDependent()) return;
405 if (Context.isSentinelNullExpr(sentinelExpr)) return;
406
407 // Pick a reasonable string to insert. Optimistically use 'nil', 'nullptr',
408 // or 'NULL' if those are actually defined in the context. Only use
409 // 'nil' for ObjC methods, where it's much more likely that the
410 // variadic arguments form a list of object pointers.
411 SourceLocation MissingNilLoc = getLocForEndOfToken(sentinelExpr->getEndLoc());
412 std::string NullValue;
413 if (calleeType == CT_Method && PP.isMacroDefined("nil"))
414 NullValue = "nil";
415 else if (getLangOpts().CPlusPlus11)
416 NullValue = "nullptr";
417 else if (PP.isMacroDefined("NULL"))
418 NullValue = "NULL";
419 else
420 NullValue = "(void*) 0";
421
422 if (MissingNilLoc.isInvalid())
423 Diag(Loc, diag::warn_missing_sentinel) << int(calleeType);
424 else
425 Diag(MissingNilLoc, diag::warn_missing_sentinel)
426 << int(calleeType)
427 << FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue);
428 Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
429}
430
431SourceRange Sema::getExprRange(Expr *E) const {
432 return E ? E->getSourceRange() : SourceRange();
433}
434
435//===----------------------------------------------------------------------===//
436// Standard Promotions and Conversions
437//===----------------------------------------------------------------------===//
438
439/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
440ExprResult Sema::DefaultFunctionArrayConversion(Expr *E, bool Diagnose) {
441 // Handle any placeholder expressions which made it here.
442 if (E->getType()->isPlaceholderType()) {
443 ExprResult result = CheckPlaceholderExpr(E);
444 if (result.isInvalid()) return ExprError();
445 E = result.get();
446 }
447
448 QualType Ty = E->getType();
449 assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type");
450
451 if (Ty->isFunctionType()) {
452 if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()))
453 if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl()))
454 if (!checkAddressOfFunctionIsAvailable(FD, Diagnose, E->getExprLoc()))
455 return ExprError();
456
457 E = ImpCastExprToType(E, Context.getPointerType(Ty),
458 CK_FunctionToPointerDecay).get();
459 } else if (Ty->isArrayType()) {
460 // In C90 mode, arrays only promote to pointers if the array expression is
461 // an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has
462 // type 'array of type' is converted to an expression that has type 'pointer
463 // to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression
464 // that has type 'array of type' ...". The relevant change is "an lvalue"
465 // (C90) to "an expression" (C99).
466 //
467 // C++ 4.2p1:
468 // An lvalue or rvalue of type "array of N T" or "array of unknown bound of
469 // T" can be converted to an rvalue of type "pointer to T".
470 //
471 if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue())
472 E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty),
473 CK_ArrayToPointerDecay).get();
474 }
475 return E;
476}
477
478static void CheckForNullPointerDereference(Sema &S, Expr *E) {
479 // Check to see if we are dereferencing a null pointer. If so,
480 // and if not volatile-qualified, this is undefined behavior that the
481 // optimizer will delete, so warn about it. People sometimes try to use this
482 // to get a deterministic trap and are surprised by clang's behavior. This
483 // only handles the pattern "*null", which is a very syntactic check.
484 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
485 if (UO->getOpcode() == UO_Deref &&
486 UO->getSubExpr()->IgnoreParenCasts()->
487 isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) &&
488 !UO->getType().isVolatileQualified()) {
489 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
490 S.PDiag(diag::warn_indirection_through_null)
491 << UO->getSubExpr()->getSourceRange());
492 S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
493 S.PDiag(diag::note_indirection_through_null));
494 }
495}
496
497static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE,
498 SourceLocation AssignLoc,
499 const Expr* RHS) {
500 const ObjCIvarDecl *IV = OIRE->getDecl();
501 if (!IV)
502 return;
503
504 DeclarationName MemberName = IV->getDeclName();
505 IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
506 if (!Member || !Member->isStr("isa"))
507 return;
508
509 const Expr *Base = OIRE->getBase();
510 QualType BaseType = Base->getType();
511 if (OIRE->isArrow())
512 BaseType = BaseType->getPointeeType();
513 if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>())
514 if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) {
515 ObjCInterfaceDecl *ClassDeclared = nullptr;
516 ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared);
517 if (!ClassDeclared->getSuperClass()
518 && (*ClassDeclared->ivar_begin()) == IV) {
519 if (RHS) {
520 NamedDecl *ObjectSetClass =
521 S.LookupSingleName(S.TUScope,
522 &S.Context.Idents.get("object_setClass"),
523 SourceLocation(), S.LookupOrdinaryName);
524 if (ObjectSetClass) {
525 SourceLocation RHSLocEnd = S.getLocForEndOfToken(RHS->getEndLoc());
526 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_assign)
527 << FixItHint::CreateInsertion(OIRE->getBeginLoc(),
528 "object_setClass(")
529 << FixItHint::CreateReplacement(
530 SourceRange(OIRE->getOpLoc(), AssignLoc), ",")
531 << FixItHint::CreateInsertion(RHSLocEnd, ")");
532 }
533 else
534 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_assign);
535 } else {
536 NamedDecl *ObjectGetClass =
537 S.LookupSingleName(S.TUScope,
538 &S.Context.Idents.get("object_getClass"),
539 SourceLocation(), S.LookupOrdinaryName);
540 if (ObjectGetClass)
541 S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_use)
542 << FixItHint::CreateInsertion(OIRE->getBeginLoc(),
543 "object_getClass(")
544 << FixItHint::CreateReplacement(
545 SourceRange(OIRE->getOpLoc(), OIRE->getEndLoc()), ")");
546 else
547 S.Diag(OIRE->getLocation(), diag::warn_objc_isa_use);
548 }
549 S.Diag(IV->getLocation(), diag::note_ivar_decl);
550 }
551 }
552}
553
554ExprResult Sema::DefaultLvalueConversion(Expr *E) {
555 if (E->getType().getQualifiers().hasOutput()) {
556 return ExprError(Diag(E->getExprLoc(), diag::err_typecheck_read_output)
557 << E->getSourceRange());
558 }
559
560 // Handle any placeholder expressions which made it here.
561 if (E->getType()->isPlaceholderType()) {
562 ExprResult result = CheckPlaceholderExpr(E);
563 if (result.isInvalid()) return ExprError();
564 E = result.get();
565 }
566
567 // C++ [conv.lval]p1:
568 // A glvalue of a non-function, non-array type T can be
569 // converted to a prvalue.
570 if (!E->isGLValue()) return E;
571
572 QualType T = E->getType();
573 assert(!T.isNull() && "r-value conversion on typeless expression?");
574
575 // We don't want to throw lvalue-to-rvalue casts on top of
576 // expressions of certain types in C++.
577 if (getLangOpts().CPlusPlus &&
578 (E->getType() == Context.OverloadTy ||
579 T->isDependentType() ||
580 T->isRecordType()))
581 return E;
582
583 // The C standard is actually really unclear on this point, and
584 // DR106 tells us what the result should be but not why. It's
585 // generally best to say that void types just doesn't undergo
586 // lvalue-to-rvalue at all. Note that expressions of unqualified
587 // 'void' type are never l-values, but qualified void can be.
588 if (T->isVoidType())
589 return E;
590
591 // OpenCL usually rejects direct accesses to values of 'half' type.
592 if (getLangOpts().OpenCL && !getOpenCLOptions().isEnabled("cl_khr_fp16") &&
593 T->isHalfType()) {
594 Diag(E->getExprLoc(), diag::err_opencl_half_load_store)
595 << 0 << T;
596 return ExprError();
597 }
598
599 CheckForNullPointerDereference(*this, E);
600 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(E->IgnoreParenCasts())) {
601 NamedDecl *ObjectGetClass = LookupSingleName(TUScope,
602 &Context.Idents.get("object_getClass"),
603 SourceLocation(), LookupOrdinaryName);
604 if (ObjectGetClass)
605 Diag(E->getExprLoc(), diag::warn_objc_isa_use)
606 << FixItHint::CreateInsertion(OISA->getBeginLoc(), "object_getClass(")
607 << FixItHint::CreateReplacement(
608 SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")");
609 else
610 Diag(E->getExprLoc(), diag::warn_objc_isa_use);
611 }
612 else if (const ObjCIvarRefExpr *OIRE =
613 dyn_cast<ObjCIvarRefExpr>(E->IgnoreParenCasts()))
614 DiagnoseDirectIsaAccess(*this, OIRE, SourceLocation(), /* Expr*/nullptr);
615
616 // C++ [conv.lval]p1:
617 // [...] If T is a non-class type, the type of the prvalue is the
618 // cv-unqualified version of T. Otherwise, the type of the
619 // rvalue is T.
620 //
621 // C99 6.3.2.1p2:
622 // If the lvalue has qualified type, the value has the unqualified
623 // version of the type of the lvalue; otherwise, the value has the
624 // type of the lvalue.
625 if (T.hasQualifiers())
626 T = T.getUnqualifiedType();
627
628 // Under the MS ABI, lock down the inheritance model now.
629 if (T->isMemberPointerType() &&
630 Context.getTargetInfo().getCXXABI().isMicrosoft())
631 (void)isCompleteType(E->getExprLoc(), T);
632
633 ExprResult Res = CheckLValueToRValueConversionOperand(E);
634 if (Res.isInvalid())
635 return Res;
636 E = Res.get();
637
638 // Loading a __weak object implicitly retains the value, so we need a cleanup to
639 // balance that.
640 if (E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
641 Cleanup.setExprNeedsCleanups(true);
642
643 Res = ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, E, nullptr,
644 VK_RValue);
645
646 // C11 6.3.2.1p2:
647 // ... if the lvalue has atomic type, the value has the non-atomic version
648 // of the type of the lvalue ...
649 if (const AtomicType *Atomic = T->getAs<AtomicType>()) {
650 T = Atomic->getValueType().getUnqualifiedType();
651 Res = ImplicitCastExpr::Create(Context, T, CK_AtomicToNonAtomic, Res.get(),
652 nullptr, VK_RValue);
653 }
654
655 return Res;
656}
657
658ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose) {
659 ExprResult Res = DefaultFunctionArrayConversion(E, Diagnose);
660 if (Res.isInvalid())
661 return ExprError();
662 Res = DefaultLvalueConversion(Res.get());
663 if (Res.isInvalid())
664 return ExprError();
665 return Res;
666}
667
668/// CallExprUnaryConversions - a special case of an unary conversion
669/// performed on a function designator of a call expression.
670ExprResult Sema::CallExprUnaryConversions(Expr *E) {
671 QualType Ty = E->getType();
672 ExprResult Res = E;
673 // Only do implicit cast for a function type, but not for a pointer
674 // to function type.
675 if (Ty->isFunctionType()) {
676 Res = ImpCastExprToType(E, Context.getPointerType(Ty),
677 CK_FunctionToPointerDecay).get();
678 if (Res.isInvalid())
679 return ExprError();
680 }
681 Res = DefaultLvalueConversion(Res.get());
682 if (Res.isInvalid())
683 return ExprError();
684 return Res.get();
685}
686
687/// UsualUnaryConversions - Performs various conversions that are common to most
688/// operators (C99 6.3). The conversions of array and function types are
689/// sometimes suppressed. For example, the array->pointer conversion doesn't
690/// apply if the array is an argument to the sizeof or address (&) operators.
691/// In these instances, this routine should *not* be called.
692ExprResult Sema::UsualUnaryConversions(Expr *E) {
693 // First, convert to an r-value.
694 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
695 if (Res.isInvalid())
696 return ExprError();
697 E = Res.get();
698
699 QualType Ty = E->getType();
700 assert(!Ty.isNull() && "UsualUnaryConversions - missing type");
701
702 // Half FP have to be promoted to float unless it is natively supported
703 if (Ty->isHalfType() && !getLangOpts().NativeHalfType)
704 return ImpCastExprToType(Res.get(), Context.FloatTy, CK_FloatingCast);
705
706 // Try to perform integral promotions if the object has a theoretically
707 // promotable type.
708 if (Ty->isIntegralOrUnscopedEnumerationType()) {
709 // C99 6.3.1.1p2:
710 //
711 // The following may be used in an expression wherever an int or
712 // unsigned int may be used:
713 // - an object or expression with an integer type whose integer
714 // conversion rank is less than or equal to the rank of int
715 // and unsigned int.
716 // - A bit-field of type _Bool, int, signed int, or unsigned int.
717 //
718 // If an int can represent all values of the original type, the
719 // value is converted to an int; otherwise, it is converted to an
720 // unsigned int. These are called the integer promotions. All
721 // other types are unchanged by the integer promotions.
722
723 QualType PTy = Context.isPromotableBitField(E);
724 if (!PTy.isNull()) {
725 E = ImpCastExprToType(E, PTy, CK_IntegralCast).get();
726 return E;
727 }
728 if (Ty->isPromotableIntegerType()) {
729 QualType PT = Context.getPromotedIntegerType(Ty);
730 E = ImpCastExprToType(E, PT, CK_IntegralCast).get();
731 return E;
732 }
733 }
734 return E;
735}
736
737/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
738/// do not have a prototype. Arguments that have type float or __fp16
739/// are promoted to double. All other argument types are converted by
740/// UsualUnaryConversions().
741ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
742 QualType Ty = E->getType();
743 assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type");
744
745 ExprResult Res = UsualUnaryConversions(E);
746 if (Res.isInvalid())
747 return ExprError();
748 E = Res.get();
749
750 // If this is a 'float' or '__fp16' (CVR qualified or typedef)
751 // promote to double.
752 // Note that default argument promotion applies only to float (and
753 // half/fp16); it does not apply to _Float16.
754 const BuiltinType *BTy = Ty->getAs<BuiltinType>();
755 if (BTy && (BTy->getKind() == BuiltinType::Half ||
756 BTy->getKind() == BuiltinType::Float)) {
757 if (getLangOpts().OpenCL &&
758 !getOpenCLOptions().isEnabled("cl_khr_fp64")) {
759 if (BTy->getKind() == BuiltinType::Half) {
760 E = ImpCastExprToType(E, Context.FloatTy, CK_FloatingCast).get();
761 }
762 } else {
763 E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).get();
764 }
765 }
766
767 // C++ performs lvalue-to-rvalue conversion as a default argument
768 // promotion, even on class types, but note:
769 // C++11 [conv.lval]p2:
770 // When an lvalue-to-rvalue conversion occurs in an unevaluated
771 // operand or a subexpression thereof the value contained in the
772 // referenced object is not accessed. Otherwise, if the glvalue
773 // has a class type, the conversion copy-initializes a temporary
774 // of type T from the glvalue and the result of the conversion
775 // is a prvalue for the temporary.
776 // FIXME: add some way to gate this entire thing for correctness in
777 // potentially potentially evaluated contexts.
778 if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) {
779 ExprResult Temp = PerformCopyInitialization(
780 InitializedEntity::InitializeTemporary(E->getType()),
781 E->getExprLoc(), E);
782 if (Temp.isInvalid())
783 return ExprError();
784 E = Temp.get();
785 }
786
787 return E;
788}
789
790/// Determine the degree of POD-ness for an expression.
791/// Incomplete types are considered POD, since this check can be performed
792/// when we're in an unevaluated context.
793Sema::VarArgKind Sema::isValidVarArgType(const QualType &Ty) {
794 if (Ty->isIncompleteType()) {
795 // C++11 [expr.call]p7:
796 // After these conversions, if the argument does not have arithmetic,
797 // enumeration, pointer, pointer to member, or class type, the program
798 // is ill-formed.
799 //
800 // Since we've already performed array-to-pointer and function-to-pointer
801 // decay, the only such type in C++ is cv void. This also handles
802 // initializer lists as variadic arguments.
803 if (Ty->isVoidType())
804 return VAK_Invalid;
805
806 if (Ty->isObjCObjectType())
807 return VAK_Invalid;
808 return VAK_Valid;
809 }
810
811 if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
812 return VAK_Invalid;
813
814 if (Ty.isCXX98PODType(Context))
815 return VAK_Valid;
816
817 // C++11 [expr.call]p7:
818 // Passing a potentially-evaluated argument of class type (Clause 9)
819 // having a non-trivial copy constructor, a non-trivial move constructor,
820 // or a non-trivial destructor, with no corresponding parameter,
821 // is conditionally-supported with implementation-defined semantics.
822 if (getLangOpts().CPlusPlus11 && !Ty->isDependentType())
823 if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl())
824 if (!Record->hasNonTrivialCopyConstructor() &&
825 !Record->hasNonTrivialMoveConstructor() &&
826 !Record->hasNonTrivialDestructor())
827 return VAK_ValidInCXX11;
828
829 if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType())
830 return VAK_Valid;
831
832 if (Ty->isObjCObjectType())
833 return VAK_Invalid;
834
835 if (getLangOpts().MSVCCompat)
836 return VAK_MSVCUndefined;
837
838 // FIXME: In C++11, these cases are conditionally-supported, meaning we're
839 // permitted to reject them. We should consider doing so.
840 return VAK_Undefined;
841}
842
843void Sema::checkVariadicArgument(const Expr *E, VariadicCallType CT) {
844 // Don't allow one to pass an Objective-C interface to a vararg.
845 const QualType &Ty = E->getType();
846 VarArgKind VAK = isValidVarArgType(Ty);
847
848 if (Ty->isCHERICapabilityType(Context))
849 if (Context.getTargetInfo().getTriple().isMIPS() &&
850 !Context.getTargetInfo().areAllPointersCapabilities())
851 Diag(E->getBeginLoc(), diag::warn_capabilities_broken_in_hybrid_varargs)
852 << E->getSourceRange();
853
854 // Complain about passing non-POD types through varargs.
855 switch (VAK) {
856 case VAK_ValidInCXX11:
857 DiagRuntimeBehavior(
858 E->getBeginLoc(), nullptr,
859 PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg) << Ty << CT);
860 LLVM_FALLTHROUGH;
861 case VAK_Valid:
862 if (Ty->isRecordType()) {
863 // This is unlikely to be what the user intended. If the class has a
864 // 'c_str' member function, the user probably meant to call that.
865 DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
866 PDiag(diag::warn_pass_class_arg_to_vararg)
867 << Ty << CT << hasCStrMethod(E) << ".c_str()");
868 }
869 break;
870
871 case VAK_Undefined:
872 case VAK_MSVCUndefined:
873 DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
874 PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg)
875 << getLangOpts().CPlusPlus11 << Ty << CT);
876 break;
877
878 case VAK_Invalid:
879 if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
880 Diag(E->getBeginLoc(),
881 diag::err_cannot_pass_non_trivial_c_struct_to_vararg)
882 << Ty << CT;
883 else if (Ty->isObjCObjectType())
884 DiagRuntimeBehavior(E->getBeginLoc(), nullptr,
885 PDiag(diag::err_cannot_pass_objc_interface_to_vararg)
886 << Ty << CT);
887 else
888 Diag(E->getBeginLoc(), diag::err_cannot_pass_to_vararg)
889 << isa<InitListExpr>(E) << Ty << CT;
890 break;
891 }
892}
893
894/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
895/// will create a trap if the resulting type is not a POD type.
896ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
897 FunctionDecl *FDecl) {
898 if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) {
899 // Strip the unbridged-cast placeholder expression off, if applicable.
900 if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast &&
901 (CT == VariadicMethod ||
902 (FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) {
903 E = stripARCUnbridgedCast(E);
904
905 // Otherwise, do normal placeholder checking.
906 } else {
907 ExprResult ExprRes = CheckPlaceholderExpr(E);
908 if (ExprRes.isInvalid())
909 return ExprError();
910 E = ExprRes.get();
911 }
912 }
913
914 ExprResult ExprRes = DefaultArgumentPromotion(E);
915 if (ExprRes.isInvalid())
916 return ExprError();
917 E = ExprRes.get();
918
919 // Diagnostics regarding non-POD argument types are
920 // emitted along with format string checking in Sema::CheckFunctionCall().
921 if (isValidVarArgType(E->getType()) == VAK_Undefined) {
922 // Turn this into a trap.
923 CXXScopeSpec SS;
924 SourceLocation TemplateKWLoc;
925 UnqualifiedId Name;
926 Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"),
927 E->getBeginLoc());
928 ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc, Name,
929 /*HasTrailingLParen=*/true,
930 /*IsAddressOfOperand=*/false);
931 if (TrapFn.isInvalid())
932 return ExprError();
933
934 ExprResult Call = BuildCallExpr(TUScope, TrapFn.get(), E->getBeginLoc(),
935 None, E->getEndLoc());
936 if (Call.isInvalid())
937 return ExprError();
938
939 ExprResult Comma =
940 ActOnBinOp(TUScope, E->getBeginLoc(), tok::comma, Call.get(), E);
941 if (Comma.isInvalid())
942 return ExprError();
943 return Comma.get();
944 }
945
946 if (!getLangOpts().CPlusPlus &&
947 RequireCompleteType(E->getExprLoc(), E->getType(),
948 diag::err_call_incomplete_argument))
949 return ExprError();
950
951 return E;
952}
953
954/// Converts an integer to complex float type. Helper function of
955/// UsualArithmeticConversions()
956///
957/// \return false if the integer expression is an integer type and is
958/// successfully converted to the complex type.
959static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr,
960 ExprResult &ComplexExpr,
961 QualType IntTy,
962 QualType ComplexTy,
963 bool SkipCast) {
964 if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true;
965 if (SkipCast) return false;
966 if (IntTy->isIntegerType()) {
967 QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType();
968 IntExpr = S.ImpCastExprToType(IntExpr.get(), fpTy, CK_IntegralToFloating);
969 IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
970 CK_FloatingRealToComplex);
971 } else {
972 assert(IntTy->isComplexIntegerType());
973 IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
974 CK_IntegralComplexToFloatingComplex);
975 }
976 return false;
977}
978
979/// Handle arithmetic conversion with complex types. Helper function of
980/// UsualArithmeticConversions()
981static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS,
982 ExprResult &RHS, QualType LHSType,
983 QualType RHSType,
984 bool IsCompAssign) {
985 // if we have an integer operand, the result is the complex type.
986 if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType,
987 /*skipCast*/false))
988 return LHSType;
989 if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType,
990 /*skipCast*/IsCompAssign))
991 return RHSType;
992
993 // This handles complex/complex, complex/float, or float/complex.
994 // When both operands are complex, the shorter operand is converted to the
995 // type of the longer, and that is the type of the result. This corresponds
996 // to what is done when combining two real floating-point operands.
997 // The fun begins when size promotion occur across type domains.
998 // From H&S 6.3.4: When one operand is complex and the other is a real
999 // floating-point type, the less precise type is converted, within it's
1000 // real or complex domain, to the precision of the other type. For example,
1001 // when combining a "long double" with a "double _Complex", the
1002 // "double _Complex" is promoted to "long double _Complex".
1003
1004 // Compute the rank of the two types, regardless of whether they are complex.
1005 int Order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
1006
1007 auto *LHSComplexType = dyn_cast<ComplexType>(LHSType);
1008 auto *RHSComplexType = dyn_cast<ComplexType>(RHSType);
1009 QualType LHSElementType =
1010 LHSComplexType ? LHSComplexType->getElementType() : LHSType;
1011 QualType RHSElementType =
1012 RHSComplexType ? RHSComplexType->getElementType() : RHSType;
1013
1014 QualType ResultType = S.Context.getComplexType(LHSElementType);
1015 if (Order < 0) {
1016 // Promote the precision of the LHS if not an assignment.
1017 ResultType = S.Context.getComplexType(RHSElementType);
1018 if (!IsCompAssign) {
1019 if (LHSComplexType)
1020 LHS =
1021 S.ImpCastExprToType(LHS.get(), ResultType, CK_FloatingComplexCast);
1022 else
1023 LHS = S.ImpCastExprToType(LHS.get(), RHSElementType, CK_FloatingCast);
1024 }
1025 } else if (Order > 0) {
1026 // Promote the precision of the RHS.
1027 if (RHSComplexType)
1028 RHS = S.ImpCastExprToType(RHS.get(), ResultType, CK_FloatingComplexCast);
1029 else
1030 RHS = S.ImpCastExprToType(RHS.get(), LHSElementType, CK_FloatingCast);
1031 }
1032 return ResultType;
1033}
1034
1035/// Handle arithmetic conversion from integer to float. Helper function
1036/// of UsualArithmeticConversions()
1037static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr,
1038 ExprResult &IntExpr,
1039 QualType FloatTy, QualType IntTy,
1040 bool ConvertFloat, bool ConvertInt) {
1041 if (IntTy->isIntegerType()) {
1042 if (ConvertInt)
1043 // Convert intExpr to the lhs floating point type.
1044 IntExpr = S.ImpCastExprToType(IntExpr.get(), FloatTy,
1045 CK_IntegralToFloating);
1046 return FloatTy;
1047 }
1048
1049 // Convert both sides to the appropriate complex float.
1050 assert(IntTy->isComplexIntegerType());
1051 QualType result = S.Context.getComplexType(FloatTy);
1052
1053 // _Complex int -> _Complex float
1054 if (ConvertInt)
1055 IntExpr = S.ImpCastExprToType(IntExpr.get(), result,
1056 CK_IntegralComplexToFloatingComplex);
1057
1058 // float -> _Complex float
1059 if (ConvertFloat)
1060 FloatExpr = S.ImpCastExprToType(FloatExpr.get(), result,
1061 CK_FloatingRealToComplex);
1062
1063 return result;
1064}
1065
1066/// Handle arithmethic conversion with floating point types. Helper
1067/// function of UsualArithmeticConversions()
1068static QualType handleFloatConversion(Sema &S, ExprResult &LHS,
1069 ExprResult &RHS, QualType LHSType,
1070 QualType RHSType, bool IsCompAssign) {
1071 bool LHSFloat = LHSType->isRealFloatingType();
1072 bool RHSFloat = RHSType->isRealFloatingType();
1073
1074 // If we have two real floating types, convert the smaller operand
1075 // to the bigger result.
1076 if (LHSFloat && RHSFloat) {
1077 int order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
1078 if (order > 0) {
1079 RHS = S.ImpCastExprToType(RHS.get(), LHSType, CK_FloatingCast);
1080 return LHSType;
1081 }
1082
1083 assert(order < 0 && "illegal float comparison");
1084 if (!IsCompAssign)
1085 LHS = S.ImpCastExprToType(LHS.get(), RHSType, CK_FloatingCast);
1086 return RHSType;
1087 }
1088
1089 if (LHSFloat) {
1090 // Half FP has to be promoted to float unless it is natively supported
1091 if (LHSType->isHalfType() && !S.getLangOpts().NativeHalfType)
1092 LHSType = S.Context.FloatTy;
1093
1094 return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType,
1095 /*convertFloat=*/!IsCompAssign,
1096 /*convertInt=*/ true);
1097 }
1098 assert(RHSFloat);
1099 return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType,
1100 /*convertInt=*/ true,
1101 /*convertFloat=*/!IsCompAssign);
1102}
1103
1104/// Diagnose attempts to convert between __float128 and long double if
1105/// there is no support for such conversion. Helper function of
1106/// UsualArithmeticConversions().
1107static bool unsupportedTypeConversion(const Sema &S, QualType LHSType,
1108 QualType RHSType) {
1109 /* No issue converting if at least one of the types is not a floating point
1110 type or the two types have the same rank.
1111 */
1112 if (!LHSType->isFloatingType() || !RHSType->isFloatingType() ||
1113 S.Context.getFloatingTypeOrder(LHSType, RHSType) == 0)
1114 return false;
1115
1116 assert(LHSType->isFloatingType() && RHSType->isFloatingType() &&
1117 "The remaining types must be floating point types.");
1118
1119 auto *LHSComplex = LHSType->getAs<ComplexType>();
1120 auto *RHSComplex = RHSType->getAs<ComplexType>();
1121
1122 QualType LHSElemType = LHSComplex ?
1123 LHSComplex->getElementType() : LHSType;
1124 QualType RHSElemType = RHSComplex ?
1125 RHSComplex->getElementType() : RHSType;
1126
1127 // No issue if the two types have the same representation
1128 if (&S.Context.getFloatTypeSemantics(LHSElemType) ==
1129 &S.Context.getFloatTypeSemantics(RHSElemType))
1130 return false;
1131
1132 bool Float128AndLongDouble = (LHSElemType == S.Context.Float128Ty &&
1133 RHSElemType == S.Context.LongDoubleTy);
1134 Float128AndLongDouble |= (LHSElemType == S.Context.LongDoubleTy &&
1135 RHSElemType == S.Context.Float128Ty);
1136
1137 // We've handled the situation where __float128 and long double have the same
1138 // representation. We allow all conversions for all possible long double types
1139 // except PPC's double double.
1140 return Float128AndLongDouble &&
1141 (&S.Context.getFloatTypeSemantics(S.Context.LongDoubleTy) ==
1142 &llvm::APFloat::PPCDoubleDouble());
1143}
1144
1145typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType);
1146
1147namespace {
1148/// These helper callbacks are placed in an anonymous namespace to
1149/// permit their use as function template parameters.
1150ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) {
1151 return S.ImpCastExprToType(op, toType, CK_IntegralCast);
1152}
1153
1154ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) {
1155 return S.ImpCastExprToType(op, S.Context.getComplexType(toType),
1156 CK_IntegralComplexCast);
1157}
1158}
1159
1160/// Handle integer arithmetic conversions. Helper function of
1161/// UsualArithmeticConversions()
1162template <PerformCastFn doLHSCast, PerformCastFn doRHSCast>
1163static QualType handleIntegerConversion(Sema &S, ExprResult &LHS,
1164 ExprResult &RHS, QualType LHSType,
1165 QualType RHSType, bool IsCompAssign) {
1166 // The rules for this case are in C99 6.3.1.8
1167 int order = S.Context.getIntegerTypeOrder(LHSType, RHSType);
1168 bool LHSSigned = LHSType->hasSignedIntegerRepresentation();
1169 bool RHSSigned = RHSType->hasSignedIntegerRepresentation();
1170 if (LHSSigned == RHSSigned) {
1171 // Same signedness; use the higher-ranked type
1172 if (order >= 0) {
1173 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1174 return LHSType;
1175 } else if (!IsCompAssign)
1176 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1177 return RHSType;
1178 } else if (order != (LHSSigned ? 1 : -1)) {
1179 // The unsigned type has greater than or equal rank to the
1180 // signed type, so use the unsigned type
1181 if (RHSSigned) {
1182 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1183 return LHSType;
1184 } else if (!IsCompAssign)
1185 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1186 return RHSType;
1187 } else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) {
1188 // The two types are different widths; if we are here, that
1189 // means the signed type is larger than the unsigned type, so
1190 // use the signed type.
1191 if (LHSSigned) {
1192 RHS = (*doRHSCast)(S, RHS.get(), LHSType);
1193 return LHSType;
1194 } else if (!IsCompAssign)
1195 LHS = (*doLHSCast)(S, LHS.get(), RHSType);
1196 return RHSType;
1197 } else {
1198 // The signed type is higher-ranked than the unsigned type,
1199 // but isn't actually any bigger (like unsigned int and long
1200 // on most 32-bit systems). Use the unsigned type corresponding
1201 // to the signed type.
1202 QualType result =
1203 S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType);
1204 RHS = (*doRHSCast)(S, RHS.get(), result);
1205 if (!IsCompAssign)
1206 LHS = (*doLHSCast)(S, LHS.get(), result);
1207 return result;
1208 }
1209}
1210
1211/// Handle conversions with GCC complex int extension. Helper function
1212/// of UsualArithmeticConversions()
1213static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
1214 ExprResult &RHS, QualType LHSType,
1215 QualType RHSType,
1216 bool IsCompAssign) {
1217 const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType();
1218 const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType();
1219
1220 if (LHSComplexInt && RHSComplexInt) {
1221 QualType LHSEltType = LHSComplexInt->getElementType();
1222 QualType RHSEltType = RHSComplexInt->getElementType();
1223 QualType ScalarType =
1224 handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast>
1225 (S, LHS, RHS, LHSEltType, RHSEltType, IsCompAssign);
1226
1227 return S.Context.getComplexType(ScalarType);
1228 }
1229
1230 if (LHSComplexInt) {
1231 QualType LHSEltType = LHSComplexInt->getElementType();
1232 QualType ScalarType =
1233 handleIntegerConversion<doComplexIntegralCast, doIntegralCast>
1234 (S, LHS, RHS, LHSEltType, RHSType, IsCompAssign);
1235 QualType ComplexType = S.Context.getComplexType(ScalarType);
1236 RHS = S.ImpCastExprToType(RHS.get(), ComplexType,
1237 CK_IntegralRealToComplex);
1238
1239 return ComplexType;
1240 }
1241
1242 assert(RHSComplexInt);
1243
1244 QualType RHSEltType = RHSComplexInt->getElementType();
1245 QualType ScalarType =
1246 handleIntegerConversion<doIntegralCast, doComplexIntegralCast>
1247 (S, LHS, RHS, LHSType, RHSEltType, IsCompAssign);
1248 QualType ComplexType = S.Context.getComplexType(ScalarType);
1249
1250 if (!IsCompAssign)
1251 LHS = S.ImpCastExprToType(LHS.get(), ComplexType,
1252 CK_IntegralRealToComplex);
1253 return ComplexType;
1254}
1255
1256/// Return the rank of a given fixed point or integer type. The value itself
1257/// doesn't matter, but the values must be increasing with proper increasing
1258/// rank as described in N1169 4.1.1.
1259static unsigned GetFixedPointRank(QualType Ty) {
1260 const auto *BTy = Ty->getAs<BuiltinType>();
1261 assert(BTy && "Expected a builtin type.");
1262
1263 switch (BTy->getKind()) {
1264 case BuiltinType::ShortFract:
1265 case BuiltinType::UShortFract:
1266 case BuiltinType::SatShortFract:
1267 case BuiltinType::SatUShortFract:
1268 return 1;
1269 case BuiltinType::Fract:
1270 case BuiltinType::UFract:
1271 case BuiltinType::SatFract:
1272 case BuiltinType::SatUFract:
1273 return 2;
1274 case BuiltinType::LongFract:
1275 case BuiltinType::ULongFract:
1276 case BuiltinType::SatLongFract:
1277 case BuiltinType::SatULongFract:
1278 return 3;
1279 case BuiltinType::ShortAccum:
1280 case BuiltinType::UShortAccum:
1281 case BuiltinType::SatShortAccum:
1282 case BuiltinType::SatUShortAccum:
1283 return 4;
1284 case BuiltinType::Accum:
1285 case BuiltinType::UAccum:
1286 case BuiltinType::SatAccum:
1287 case BuiltinType::SatUAccum:
1288 return 5;
1289 case BuiltinType::LongAccum:
1290 case BuiltinType::ULongAccum:
1291 case BuiltinType::SatLongAccum:
1292 case BuiltinType::SatULongAccum:
1293 return 6;
1294 default:
1295 if (BTy->isInteger())
1296 return 0;
1297 llvm_unreachable("Unexpected fixed point or integer type");
1298 }
1299}
1300
1301/// handleFixedPointConversion - Fixed point operations between fixed
1302/// point types and integers or other fixed point types do not fall under
1303/// usual arithmetic conversion since these conversions could result in loss
1304/// of precsision (N1169 4.1.4). These operations should be calculated with
1305/// the full precision of their result type (N1169 4.1.6.2.1).
1306static QualType handleFixedPointConversion(Sema &S, QualType LHSTy,
1307 QualType RHSTy) {
1308 assert((LHSTy->isFixedPointType() || RHSTy->isFixedPointType()) &&
1309 "Expected at least one of the operands to be a fixed point type");
1310 assert((LHSTy->isFixedPointOrIntegerType() ||
1311 RHSTy->isFixedPointOrIntegerType()) &&
1312 "Special fixed point arithmetic operation conversions are only "
1313 "applied to ints or other fixed point types");
1314
1315 // If one operand has signed fixed-point type and the other operand has
1316 // unsigned fixed-point type, then the unsigned fixed-point operand is
1317 // converted to its corresponding signed fixed-point type and the resulting
1318 // type is the type of the converted operand.
1319 if (RHSTy->isSignedFixedPointType() && LHSTy->isUnsignedFixedPointType())
1320 LHSTy = S.Context.getCorrespondingSignedFixedPointType(LHSTy);
1321 else if (RHSTy->isUnsignedFixedPointType() && LHSTy->isSignedFixedPointType())
1322 RHSTy = S.Context.getCorrespondingSignedFixedPointType(RHSTy);
1323
1324 // The result type is the type with the highest rank, whereby a fixed-point
1325 // conversion rank is always greater than an integer conversion rank; if the
1326 // type of either of the operands is a saturating fixedpoint type, the result
1327 // type shall be the saturating fixed-point type corresponding to the type
1328 // with the highest rank; the resulting value is converted (taking into
1329 // account rounding and overflow) to the precision of the resulting type.
1330 // Same ranks between signed and unsigned types are resolved earlier, so both
1331 // types are either signed or both unsigned at this point.
1332 unsigned LHSTyRank = GetFixedPointRank(LHSTy);
1333 unsigned RHSTyRank = GetFixedPointRank(RHSTy);
1334
1335 QualType ResultTy = LHSTyRank > RHSTyRank ? LHSTy : RHSTy;
1336
1337 if (LHSTy->isSaturatedFixedPointType() || RHSTy->isSaturatedFixedPointType())
1338 ResultTy = S.Context.getCorrespondingSaturatedType(ResultTy);
1339
1340 return ResultTy;
1341}
1342
1343/// UsualArithmeticConversions - Performs various conversions that are common to
1344/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
1345/// routine returns the first non-arithmetic type found. The client is
1346/// responsible for emitting appropriate error diagnostics.
1347QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
1348 bool IsCompAssign) {
1349 if (!IsCompAssign) {
1350 LHS = UsualUnaryConversions(LHS.get());
1351 if (LHS.isInvalid())
1352 return QualType();
1353 }
1354
1355 RHS = UsualUnaryConversions(RHS.get());
1356 if (RHS.isInvalid())
1357 return QualType();
1358
1359 // For conversion purposes, we ignore any qualifiers.
1360 // For example, "const float" and "float" are equivalent.
1361 QualType LHSType =
1362 Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
1363 QualType RHSType =
1364 Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
1365
1366 // For conversion purposes, we ignore any atomic qualifier on the LHS.
1367 if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>())
1368 LHSType = AtomicLHS->getValueType();
1369
1370 // If both types are identical, no conversion is needed.
1371 if (LHSType == RHSType)
1372 return LHSType;
1373
1374 // If either side is a non-arithmetic type (e.g. a pointer), we are done.
1375 // The caller can deal with this (e.g. pointer + int).
1376 if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
1377 return QualType();
1378
1379 // Apply unary and bitfield promotions to the LHS's type.
1380 QualType LHSUnpromotedType = LHSType;
1381 if (LHSType->isPromotableIntegerType())
1382 LHSType = Context.getPromotedIntegerType(LHSType);
1383 QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get());
1384 if (!LHSBitfieldPromoteTy.isNull())
1385 LHSType = LHSBitfieldPromoteTy;
1386 if (LHSType != LHSUnpromotedType && !IsCompAssign)
1387 LHS = ImpCastExprToType(LHS.get(), LHSType, CK_IntegralCast);
1388
1389 // If both types are identical, no conversion is needed.
1390 if (LHSType == RHSType)
1391 return LHSType;
1392
1393 // At this point, we have two different arithmetic types.
1394
1395 // Diagnose attempts to convert between __float128 and long double where
1396 // such conversions currently can't be handled.
1397 if (unsupportedTypeConversion(*this, LHSType, RHSType))
1398 return QualType();
1399
1400 // Handle complex types first (C99 6.3.1.8p1).
1401 if (LHSType->isComplexType() || RHSType->isComplexType())
1402 return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType,
1403 IsCompAssign);
1404
1405 // Now handle "real" floating types (i.e. float, double, long double).
1406 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
1407 return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType,
1408 IsCompAssign);
1409
1410 // Handle GCC complex int extension.
1411 if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType())
1412 return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType,
1413 IsCompAssign);
1414
1415 if (LHSType->isFixedPointType() || RHSType->isFixedPointType())
1416 return handleFixedPointConversion(*this, LHSType, RHSType);
1417
1418 // Finally, we have two differing integer types.
1419 return handleIntegerConversion<doIntegralCast, doIntegralCast>
1420 (*this, LHS, RHS, LHSType, RHSType, IsCompAssign);
1421}
1422
1423//===----------------------------------------------------------------------===//
1424// Semantic Analysis for various Expression Types
1425//===----------------------------------------------------------------------===//
1426
1427
1428ExprResult
1429Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc,
1430 SourceLocation DefaultLoc,
1431 SourceLocation RParenLoc,
1432 Expr *ControllingExpr,
1433 ArrayRef<ParsedType> ArgTypes,
1434 ArrayRef<Expr *> ArgExprs) {
1435 unsigned NumAssocs = ArgTypes.size();
1436 assert(NumAssocs == ArgExprs.size());
1437
1438 TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs];
1439 for (unsigned i = 0; i < NumAssocs; ++i) {
1440 if (ArgTypes[i])
1441 (void) GetTypeFromParser(ArgTypes[i], &Types[i]);
1442 else
1443 Types[i] = nullptr;
1444 }
1445
1446 ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc,
1447 ControllingExpr,
1448 llvm::makeArrayRef(Types, NumAssocs),
1449 ArgExprs);
1450 delete [] Types;
1451 return ER;
1452}
1453
1454ExprResult
1455Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc,
1456 SourceLocation DefaultLoc,
1457 SourceLocation RParenLoc,
1458 Expr *ControllingExpr,
1459 ArrayRef<TypeSourceInfo *> Types,
1460 ArrayRef<Expr *> Exprs) {
1461 unsigned NumAssocs = Types.size();
1462 assert(NumAssocs == Exprs.size());
1463
1464 // Decay and strip qualifiers for the controlling expression type, and handle
1465 // placeholder type replacement. See committee discussion from WG14 DR423.
1466 {
1467 EnterExpressionEvaluationContext Unevaluated(
1468 *this, Sema::ExpressionEvaluationContext::Unevaluated);
1469 ExprResult R = DefaultFunctionArrayLvalueConversion(ControllingExpr);
1470 if (R.isInvalid())
1471 return ExprError();
1472 ControllingExpr = R.get();
1473 }
1474
1475 // The controlling expression is an unevaluated operand, so side effects are
1476 // likely unintended.
1477 if (!inTemplateInstantiation() &&
1478 ControllingExpr->HasSideEffects(Context, false))
1479 Diag(ControllingExpr->getExprLoc(),
1480 diag::warn_side_effects_unevaluated_context);
1481
1482 bool TypeErrorFound = false,
1483 IsResultDependent = ControllingExpr->isTypeDependent(),
1484 ContainsUnexpandedParameterPack
1485 = ControllingExpr->containsUnexpandedParameterPack();
1486
1487 for (unsigned i = 0; i < NumAssocs; ++i) {
1488 if (Exprs[i]->containsUnexpandedParameterPack())
1489 ContainsUnexpandedParameterPack = true;
1490
1491 if (Types[i]) {
1492 if (Types[i]->getType()->containsUnexpandedParameterPack())
1493 ContainsUnexpandedParameterPack = true;
1494
1495 if (Types[i]->getType()->isDependentType()) {
1496 IsResultDependent = true;
1497 } else {
1498 // C11 6.5.1.1p2 "The type name in a generic association shall specify a
1499 // complete object type other than a variably modified type."
1500 unsigned D = 0;
1501 if (Types[i]->getType()->isIncompleteType())
1502 D = diag::err_assoc_type_incomplete;
1503 else if (!Types[i]->getType()->isObjectType())
1504 D = diag::err_assoc_type_nonobject;
1505 else if (Types[i]->getType()->isVariablyModifiedType())
1506 D = diag::err_assoc_type_variably_modified;
1507
1508 if (D != 0) {
1509 Diag(Types[i]->getTypeLoc().getBeginLoc(), D)
1510 << Types[i]->getTypeLoc().getSourceRange()
1511 << Types[i]->getType();
1512 TypeErrorFound = true;
1513 }
1514
1515 // C11 6.5.1.1p2 "No two generic associations in the same generic
1516 // selection shall specify compatible types."
1517 for (unsigned j = i+1; j < NumAssocs; ++j)
1518 if (Types[j] && !Types[j]->getType()->isDependentType() &&
1519 Context.typesAreCompatible(Types[i]->getType(),
1520 Types[j]->getType())) {
1521 Diag(Types[j]->getTypeLoc().getBeginLoc(),
1522 diag::err_assoc_compatible_types)
1523 << Types[j]->getTypeLoc().getSourceRange()
1524 << Types[j]->getType()
1525 << Types[i]->getType();
1526 Diag(Types[i]->getTypeLoc().getBeginLoc(),
1527 diag::note_compat_assoc)
1528 << Types[i]->getTypeLoc().getSourceRange()
1529 << Types[i]->getType();
1530 TypeErrorFound = true;
1531 }
1532 }
1533 }
1534 }
1535 if (TypeErrorFound)
1536 return ExprError();
1537
1538 // If we determined that the generic selection is result-dependent, don't
1539 // try to compute the result expression.
1540 if (IsResultDependent)
1541 return GenericSelectionExpr::Create(Context, KeyLoc, ControllingExpr, Types,
1542 Exprs, DefaultLoc, RParenLoc,
1543 ContainsUnexpandedParameterPack);
1544
1545 SmallVector<unsigned, 1> CompatIndices;
1546 unsigned DefaultIndex = -1U;
1547 for (unsigned i = 0; i < NumAssocs; ++i) {
1548 if (!Types[i])
1549 DefaultIndex = i;
1550 else if (Context.typesAreCompatible(ControllingExpr->getType(),
1551 Types[i]->getType()))
1552 CompatIndices.push_back(i);
1553 }
1554
1555 // C11 6.5.1.1p2 "The controlling expression of a generic selection shall have
1556 // type compatible with at most one of the types named in its generic
1557 // association list."
1558 if (CompatIndices.size() > 1) {
1559 // We strip parens here because the controlling expression is typically
1560 // parenthesized in macro definitions.
1561 ControllingExpr = ControllingExpr->IgnoreParens();
1562 Diag(ControllingExpr->getBeginLoc(), diag::err_generic_sel_multi_match)
1563 << ControllingExpr->getSourceRange() << ControllingExpr->getType()
1564 << (unsigned)CompatIndices.size();
1565 for (unsigned I : CompatIndices) {
1566 Diag(Types[I]->getTypeLoc().getBeginLoc(),
1567 diag::note_compat_assoc)
1568 << Types[I]->getTypeLoc().getSourceRange()
1569 << Types[I]->getType();
1570 }
1571 return ExprError();
1572 }
1573
1574 // C11 6.5.1.1p2 "If a generic selection has no default generic association,
1575 // its controlling expression shall have type compatible with exactly one of
1576 // the types named in its generic association list."
1577 if (DefaultIndex == -1U && CompatIndices.size() == 0) {
1578 // We strip parens here because the controlling expression is typically
1579 // parenthesized in macro definitions.
1580 ControllingExpr = ControllingExpr->IgnoreParens();
1581 Diag(ControllingExpr->getBeginLoc(), diag::err_generic_sel_no_match)
1582 << ControllingExpr->getSourceRange() << ControllingExpr->getType();
1583 return ExprError();
1584 }
1585
1586 // C11 6.5.1.1p3 "If a generic selection has a generic association with a
1587 // type name that is compatible with the type of the controlling expression,
1588 // then the result expression of the generic selection is the expression
1589 // in that generic association. Otherwise, the result expression of the
1590 // generic selection is the expression in the default generic association."
1591 unsigned ResultIndex =
1592 CompatIndices.size() ? CompatIndices[0] : DefaultIndex;
1593
1594 return GenericSelectionExpr::Create(
1595 Context, KeyLoc, ControllingExpr, Types, Exprs, DefaultLoc, RParenLoc,
1596 ContainsUnexpandedParameterPack, ResultIndex);
1597}
1598
1599/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the
1600/// location of the token and the offset of the ud-suffix within it.
1601static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc,
1602 unsigned Offset) {
1603 return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(),
1604 S.getLangOpts());
1605}
1606
1607/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up
1608/// the corresponding cooked (non-raw) literal operator, and build a call to it.
1609static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope,
1610 IdentifierInfo *UDSuffix,
1611 SourceLocation UDSuffixLoc,
1612 ArrayRef<Expr*> Args,
1613 SourceLocation LitEndLoc) {
1614 assert(Args.size() <= 2 && "too many arguments for literal operator");
1615
1616 QualType ArgTy[2];
1617 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
1618 ArgTy[ArgIdx] = Args[ArgIdx]->getType();
1619 if (ArgTy[ArgIdx]->isArrayType())
1620 ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]);
1621 }
1622
1623 DeclarationName OpName =
1624 S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
1625 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
1626 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
1627
1628 LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName);
1629 if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()),
1630 /*AllowRaw*/ false, /*AllowTemplate*/ false,
1631 /*AllowStringTemplate*/ false,
1632 /*DiagnoseMissing*/ true) == Sema::LOLR_Error)
1633 return ExprError();
1634
1635 return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc);
1636}
1637
1638/// ActOnStringLiteral - The specified tokens were lexed as pasted string
1639/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string
1640/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from
1641/// multiple tokens. However, the common case is that StringToks points to one
1642/// string.
1643///
1644ExprResult
1645Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
1646 assert(!StringToks.empty() && "Must have at least one string!");
1647
1648 StringLiteralParser Literal(StringToks, PP);
1649 if (Literal.hadError)
1650 return ExprError();
1651
1652 SmallVector<SourceLocation, 4> StringTokLocs;
1653 for (const Token &Tok : StringToks)
1654 StringTokLocs.push_back(Tok.getLocation());
1655
1656 QualType CharTy = Context.CharTy;
1657 StringLiteral::StringKind Kind = StringLiteral::Ascii;
1658 if (Literal.isWide()) {
1659 CharTy = Context.getWideCharType();
1660 Kind = StringLiteral::Wide;
1661 } else if (Literal.isUTF8()) {
1662 if (getLangOpts().Char8)
1663 CharTy = Context.Char8Ty;
1664 Kind = StringLiteral::UTF8;
1665 } else if (Literal.isUTF16()) {
1666 CharTy = Context.Char16Ty;
1667 Kind = StringLiteral::UTF16;
1668 } else if (Literal.isUTF32()) {
1669 CharTy = Context.Char32Ty;
1670 Kind = StringLiteral::UTF32;
1671 } else if (Literal.isPascal()) {
1672 CharTy = Context.UnsignedCharTy;
1673 }
1674
1675 // Warn on initializing an array of char from a u8 string literal; this
1676 // becomes ill-formed in C++2a.
1677 if (getLangOpts().CPlusPlus && !getLangOpts().CPlusPlus2a &&
1678 !getLangOpts().Char8 && Kind == StringLiteral::UTF8) {
1679 Diag(StringTokLocs.front(), diag::warn_cxx2a_compat_utf8_string);
1680
1681 // Create removals for all 'u8' prefixes in the string literal(s). This
1682 // ensures C++2a compatibility (but may change the program behavior when
1683 // built by non-Clang compilers for which the execution character set is
1684 // not always UTF-8).
1685 auto RemovalDiag = PDiag(diag::note_cxx2a_compat_utf8_string_remove_u8);
1686 SourceLocation RemovalDiagLoc;
1687 for (const Token &Tok : StringToks) {
1688 if (Tok.getKind() == tok::utf8_string_literal) {
1689 if (RemovalDiagLoc.isInvalid())
1690 RemovalDiagLoc = Tok.getLocation();
1691 RemovalDiag << FixItHint::CreateRemoval(CharSourceRange::getCharRange(
1692 Tok.getLocation(),
1693 Lexer::AdvanceToTokenCharacter(Tok.getLocation(), 2,
1694 getSourceManager(), getLangOpts())));
1695 }
1696 }
1697 Diag(RemovalDiagLoc, RemovalDiag);
1698 }
1699
1700 QualType StrTy =
1701 Context.getStringLiteralArrayType(CharTy, Literal.GetNumStringChars());
1702
1703 // Pass &StringTokLocs[0], StringTokLocs.size() to factory!
1704 StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(),
1705 Kind, Literal.Pascal, StrTy,
1706 &StringTokLocs[0],
1707 StringTokLocs.size());
1708 if (Literal.getUDSuffix().empty())
1709 return Lit;
1710
1711 // We're building a user-defined literal.
1712 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
1713 SourceLocation UDSuffixLoc =
1714 getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()],
1715 Literal.getUDSuffixOffset());
1716
1717 // Make sure we're allowed user-defined literals here.
1718 if (!UDLScope)
1719 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl));
1720
1721 // C++11 [lex.ext]p5: The literal L is treated as a call of the form
1722 // operator "" X (str, len)
1723 QualType SizeType = Context.getSizeType();
1724
1725 DeclarationName OpName =
1726 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
1727 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
1728 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
1729
1730 QualType ArgTy[] = {
1731 Context.getArrayDecayedType(StrTy), SizeType
1732 };
1733
1734 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
1735 switch (LookupLiteralOperator(UDLScope, R, ArgTy,
1736 /*AllowRaw*/ false, /*AllowTemplate*/ false,
1737 /*AllowStringTemplate*/ true,
1738 /*DiagnoseMissing*/ true)) {
1739
1740 case LOLR_Cooked: {
1741 llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars());
1742 IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType,
1743 StringTokLocs[0]);
1744 Expr *Args[] = { Lit, LenArg };
1745
1746 return BuildLiteralOperatorCall(R, OpNameInfo, Args, StringTokLocs.back());
1747 }
1748
1749 case LOLR_StringTemplate: {
1750 TemplateArgumentListInfo ExplicitArgs;
1751
1752 unsigned CharBits = Context.getIntWidth(CharTy);
1753 bool CharIsUnsigned = CharTy->isUnsignedIntegerType();
1754 llvm::APSInt Value(CharBits, CharIsUnsigned);
1755
1756 TemplateArgument TypeArg(CharTy);
1757 TemplateArgumentLocInfo TypeArgInfo(Context.getTrivialTypeSourceInfo(CharTy));
1758 ExplicitArgs.addArgument(TemplateArgumentLoc(TypeArg, TypeArgInfo));
1759
1760 for (unsigned I = 0, N = Lit->getLength(); I != N; ++I) {
1761 Value = Lit->getCodeUnit(I);
1762 TemplateArgument Arg(Context, Value, CharTy);
1763 TemplateArgumentLocInfo ArgInfo;
1764 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
1765 }
1766 return BuildLiteralOperatorCall(R, OpNameInfo, None, StringTokLocs.back(),
1767 &ExplicitArgs);
1768 }
1769 case LOLR_Raw:
1770 case LOLR_Template:
1771 case LOLR_ErrorNoDiagnostic:
1772 llvm_unreachable("unexpected literal operator lookup result");
1773 case LOLR_Error:
1774 return ExprError();
1775 }
1776 llvm_unreachable("unexpected literal operator lookup result");
1777}
1778
1779DeclRefExpr *
1780Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
1781 SourceLocation Loc,
1782 const CXXScopeSpec *SS) {
1783 DeclarationNameInfo NameInfo(D->getDeclName(), Loc);
1784 return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS);
1785}
1786
1787DeclRefExpr *
1788Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
1789 const DeclarationNameInfo &NameInfo,
1790 const CXXScopeSpec *SS, NamedDecl *FoundD,
1791 SourceLocation TemplateKWLoc,
1792 const TemplateArgumentListInfo *TemplateArgs) {
1793 NestedNameSpecifierLoc NNS =
1794 SS ? SS->getWithLocInContext(Context) : NestedNameSpecifierLoc();
1795 return BuildDeclRefExpr(D, Ty, VK, NameInfo, NNS, FoundD, TemplateKWLoc,
1796 TemplateArgs);
1797}
1798
1799NonOdrUseReason Sema::getNonOdrUseReasonInCurrentContext(ValueDecl *D) {
1800 // A declaration named in an unevaluated operand never constitutes an odr-use.
1801 if (isUnevaluatedContext())
1802 return NOUR_Unevaluated;
1803
1804 // C++2a [basic.def.odr]p4:
1805 // A variable x whose name appears as a potentially-evaluated expression e
1806 // is odr-used by e unless [...] x is a reference that is usable in
1807 // constant expressions.
1808 if (VarDecl *VD = dyn_cast<VarDecl>(D)) {
1809 if (VD->getType()->isReferenceType() &&
1810 !(getLangOpts().OpenMP && isOpenMPCapturedDecl(D)) &&
1811 VD->isUsableInConstantExpressions(Context))
1812 return NOUR_Constant;
1813 }
1814
1815 // All remaining non-variable cases constitute an odr-use. For variables, we
1816 // need to wait and see how the expression is used.
1817 return NOUR_None;
1818}
1819
1820/// BuildDeclRefExpr - Build an expression that references a
1821/// declaration that does not require a closure capture.
1822DeclRefExpr *
1823Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
1824 const DeclarationNameInfo &NameInfo,
1825 NestedNameSpecifierLoc NNS, NamedDecl *FoundD,
1826 SourceLocation TemplateKWLoc,
1827 const TemplateArgumentListInfo *TemplateArgs) {
1828 bool RefersToCapturedVariable =
1829 isa<VarDecl>(D) &&
1830 NeedToCaptureVariable(cast<VarDecl>(D), NameInfo.getLoc());
1831
1832 DeclRefExpr *E = DeclRefExpr::Create(
1833 Context, NNS, TemplateKWLoc, D, RefersToCapturedVariable, NameInfo, Ty,
1834 VK, FoundD, TemplateArgs, getNonOdrUseReasonInCurrentContext(D));
1835 MarkDeclRefReferenced(E);
1836
1837 if (getLangOpts().ObjCWeak && isa<VarDecl>(D) &&
1838 Ty.getObjCLifetime() == Qualifiers::OCL_Weak && !isUnevaluatedContext() &&
1839 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, E->getBeginLoc()))
1840 getCurFunction()->recordUseOfWeak(E);
1841
1842 FieldDecl *FD = dyn_cast<FieldDecl>(D);
1843 if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(D))
1844 FD = IFD->getAnonField();
1845 if (FD) {
1846 UnusedPrivateFields.remove(FD);
1847 // Just in case we're building an illegal pointer-to-member.
1848 if (FD->isBitField())
1849 E->setObjectKind(OK_BitField);
1850 }
1851
1852 // C++ [expr.prim]/8: The expression [...] is a bit-field if the identifier
1853 // designates a bit-field.
1854 if (auto *BD = dyn_cast<BindingDecl>(D))
1855 if (auto *BE = BD->getBinding())
1856 E->setObjectKind(BE->getObjectKind());
1857
1858 return E;
1859}
1860
1861/// Decomposes the given name into a DeclarationNameInfo, its location, and
1862/// possibly a list of template arguments.
1863///
1864/// If this produces template arguments, it is permitted to call
1865/// DecomposeTemplateName.
1866///
1867/// This actually loses a lot of source location information for
1868/// non-standard name kinds; we should consider preserving that in
1869/// some way.
1870void
1871Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
1872 TemplateArgumentListInfo &Buffer,
1873 DeclarationNameInfo &NameInfo,
1874 const TemplateArgumentListInfo *&TemplateArgs) {
1875 if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId) {
1876 Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
1877 Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
1878
1879 ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(),
1880 Id.TemplateId->NumArgs);
1881 translateTemplateArguments(TemplateArgsPtr, Buffer);
1882
1883 TemplateName TName = Id.TemplateId->Template.get();
1884 SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc;
1885 NameInfo = Context.getNameForTemplate(TName, TNameLoc);
1886 TemplateArgs = &Buffer;
1887 } else {
1888 NameInfo = GetNameFromUnqualifiedId(Id);
1889 TemplateArgs = nullptr;
1890 }
1891}
1892
1893static void emitEmptyLookupTypoDiagnostic(
1894 const TypoCorrection &TC, Sema &SemaRef, const CXXScopeSpec &SS,
1895 DeclarationName Typo, SourceLocation TypoLoc, ArrayRef<Expr *> Args,
1896 unsigned DiagnosticID, unsigned DiagnosticSuggestID) {
1897 DeclContext *Ctx =
1898 SS.isEmpty() ? nullptr : SemaRef.computeDeclContext(SS, false);
1899 if (!TC) {
1900 // Emit a special diagnostic for failed member lookups.
1901 // FIXME: computing the declaration context might fail here (?)
1902 if (Ctx)
1903 SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << Ctx
1904 << SS.getRange();
1905 else
1906 SemaRef.Diag(TypoLoc, DiagnosticID) << Typo;
1907 return;
1908 }
1909
1910 std::string CorrectedStr = TC.getAsString(SemaRef.getLangOpts());
1911 bool DroppedSpecifier =
1912 TC.WillReplaceSpecifier() && Typo.getAsString() == CorrectedStr;
1913 unsigned NoteID = TC.getCorrectionDeclAs<ImplicitParamDecl>()
1914 ? diag::note_implicit_param_decl
1915 : diag::note_previous_decl;
1916 if (!Ctx)
1917 SemaRef.diagnoseTypo(TC, SemaRef.PDiag(DiagnosticSuggestID) << Typo,
1918 SemaRef.PDiag(NoteID));
1919 else
1920 SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest)
1921 << Typo << Ctx << DroppedSpecifier
1922 << SS.getRange(),
1923 SemaRef.PDiag(NoteID));
1924}
1925
1926/// Diagnose an empty lookup.
1927///
1928/// \return false if new lookup candidates were found
1929bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
1930 CorrectionCandidateCallback &CCC,
1931 TemplateArgumentListInfo *ExplicitTemplateArgs,
1932 ArrayRef<Expr *> Args, TypoExpr **Out) {
1933 DeclarationName Name = R.getLookupName();
1934
1935 unsigned diagnostic = diag::err_undeclared_var_use;
1936 unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest;
1937 if (Name.getNameKind() == DeclarationName::CXXOperatorName ||
1938 Name.getNameKind() == DeclarationName::CXXLiteralOperatorName ||
1939 Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
1940 diagnostic = diag::err_undeclared_use;
1941 diagnostic_suggest = diag::err_undeclared_use_suggest;
1942 }
1943
1944 // If the original lookup was an unqualified lookup, fake an
1945 // unqualified lookup. This is useful when (for example) the
1946 // original lookup would not have found something because it was a
1947 // dependent name.
1948 DeclContext *DC = SS.isEmpty() ? CurContext : nullptr;
1949 while (DC) {
1950 if (isa<CXXRecordDecl>(DC)) {
1951 LookupQualifiedName(R, DC);
1952
1953 if (!R.empty()) {
1954 // Don't give errors about ambiguities in this lookup.
1955 R.suppressDiagnostics();
1956
1957 // During a default argument instantiation the CurContext points
1958 // to a CXXMethodDecl; but we can't apply a this-> fixit inside a
1959 // function parameter list, hence add an explicit check.
1960 bool isDefaultArgument =
1961 !CodeSynthesisContexts.empty() &&
1962 CodeSynthesisContexts.back().Kind ==
1963 CodeSynthesisContext::DefaultFunctionArgumentInstantiation;
1964 CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext);
1965 bool isInstance = CurMethod &&
1966 CurMethod->isInstance() &&
1967 DC == CurMethod->getParent() && !isDefaultArgument;
1968
1969 // Give a code modification hint to insert 'this->'.
1970 // TODO: fixit for inserting 'Base<T>::' in the other cases.
1971 // Actually quite difficult!
1972 if (getLangOpts().MSVCCompat)
1973 diagnostic = diag::ext_found_via_dependent_bases_lookup;
1974 if (isInstance) {
1975 Diag(R.getNameLoc(), diagnostic) << Name
1976 << FixItHint::CreateInsertion(R.getNameLoc(), "this->");
1977 CheckCXXThisCapture(R.getNameLoc());
1978 } else {
1979 Diag(R.getNameLoc(), diagnostic) << Name;
1980 }
1981
1982 // Do we really want to note all of these?
1983 for (NamedDecl *D : R)
1984 Diag(D->getLocation(), diag::note_dependent_var_use);
1985
1986 // Return true if we are inside a default argument instantiation
1987 // and the found name refers to an instance member function, otherwise
1988 // the function calling DiagnoseEmptyLookup will try to create an
1989 // implicit member call and this is wrong for default argument.
1990 if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) {
1991 Diag(R.getNameLoc(), diag::err_member_call_without_object);
1992 return true;
1993 }
1994
1995 // Tell the callee to try to recover.
1996 return false;
1997 }
1998
1999 R.clear();
2000 }
2001
2002 // In Microsoft mode, if we are performing lookup from within a friend
2003 // function definition declared at class scope then we must set
2004 // DC to the lexical parent to be able to search into the parent
2005 // class.
2006 if (getLangOpts().MSVCCompat && isa<FunctionDecl>(DC) &&
2007 cast<FunctionDecl>(DC)->getFriendObjectKind() &&
2008 DC->getLexicalParent()->isRecord())
2009 DC = DC->getLexicalParent();
2010 else
2011 DC = DC->getParent();
2012 }
2013
2014 // We didn't find anything, so try to correct for a typo.
2015 TypoCorrection Corrected;
2016 if (S && Out) {
2017 SourceLocation TypoLoc = R.getNameLoc();
2018 assert(!ExplicitTemplateArgs &&
2019 "Diagnosing an empty lookup with explicit template args!");
2020 *Out = CorrectTypoDelayed(
2021 R.getLookupNameInfo(), R.getLookupKind(), S, &SS, CCC,
2022 [=](const TypoCorrection &TC) {
2023 emitEmptyLookupTypoDiagnostic(TC, *this, SS, Name, TypoLoc, Args,
2024 diagnostic, diagnostic_suggest);
2025 },
2026 nullptr, CTK_ErrorRecovery);
2027 if (*Out)
2028 return true;
2029 } else if (S &&
2030 (Corrected = CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(),
2031 S, &SS, CCC, CTK_ErrorRecovery))) {
2032 std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
2033 bool DroppedSpecifier =
2034 Corrected.WillReplaceSpecifier() && Name.getAsString() == CorrectedStr;
2035 R.setLookupName(Corrected.getCorrection());
2036
2037 bool AcceptableWithRecovery = false;
2038 bool AcceptableWithoutRecovery = false;
2039 NamedDecl *ND = Corrected.getFoundDecl();
2040 if (ND) {
2041 if (Corrected.isOverloaded()) {
2042 OverloadCandidateSet OCS(R.getNameLoc(),
2043 OverloadCandidateSet::CSK_Normal);
2044 OverloadCandidateSet::iterator Best;
2045 for (NamedDecl *CD : Corrected) {
2046 if (FunctionTemplateDecl *FTD =
2047 dyn_cast<FunctionTemplateDecl>(CD))
2048 AddTemplateOverloadCandidate(
2049 FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs,
2050 Args, OCS);
2051 else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
2052 if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0)
2053 AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none),
2054 Args, OCS);
2055 }
2056 switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) {
2057 case OR_Success:
2058 ND = Best->FoundDecl;
2059 Corrected.setCorrectionDecl(ND);
2060 break;
2061 default:
2062 // FIXME: Arbitrarily pick the first declaration for the note.
2063 Corrected.setCorrectionDecl(ND);
2064 break;
2065 }
2066 }
2067 R.addDecl(ND);
2068 if (getLangOpts().CPlusPlus && ND->isCXXClassMember()) {
2069 CXXRecordDecl *Record = nullptr;
2070 if (Corrected.getCorrectionSpecifier()) {
2071 const Type *Ty = Corrected.getCorrectionSpecifier()->getAsType();
2072 Record = Ty->getAsCXXRecordDecl();
2073 }
2074 if (!Record)
2075 Record = cast<CXXRecordDecl>(
2076 ND->getDeclContext()->getRedeclContext());
2077 R.setNamingClass(Record);
2078 }
2079
2080 auto *UnderlyingND = ND->getUnderlyingDecl();
2081 AcceptableWithRecovery = isa<ValueDecl>(UnderlyingND) ||
2082 isa<FunctionTemplateDecl>(UnderlyingND);
2083 // FIXME: If we ended up with a typo for a type name or
2084 // Objective-C class name, we're in trouble because the parser
2085 // is in the wrong place to recover. Suggest the typo
2086 // correction, but don't make it a fix-it since we're not going
2087 // to recover well anyway.
2088 AcceptableWithoutRecovery = isa<TypeDecl>(UnderlyingND) ||
2089 getAsTypeTemplateDecl(UnderlyingND) ||
2090 isa<ObjCInterfaceDecl>(UnderlyingND);
2091 } else {
2092 // FIXME: We found a keyword. Suggest it, but don't provide a fix-it
2093 // because we aren't able to recover.
2094 AcceptableWithoutRecovery = true;
2095 }
2096
2097 if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
2098 unsigned NoteID = Corrected.getCorrectionDeclAs<ImplicitParamDecl>()
2099 ? diag::note_implicit_param_decl
2100 : diag::note_previous_decl;
2101 if (SS.isEmpty())
2102 diagnoseTypo(Corrected, PDiag(diagnostic_suggest) << Name,
2103 PDiag(NoteID), AcceptableWithRecovery);
2104 else
2105 diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
2106 << Name << computeDeclContext(SS, false)
2107 << DroppedSpecifier << SS.getRange(),
2108 PDiag(NoteID), AcceptableWithRecovery);
2109
2110 // Tell the callee whether to try to recover.
2111 return !AcceptableWithRecovery;
2112 }
2113 }
2114 R.clear();
2115
2116 // Emit a special diagnostic for failed member lookups.
2117 // FIXME: computing the declaration context might fail here (?)
2118 if (!SS.isEmpty()) {
2119 Diag(R.getNameLoc(), diag::err_no_member)
2120 << Name << computeDeclContext(SS, false)
2121 << SS.getRange();
2122 return true;
2123 }
2124
2125 // Give up, we can't recover.
2126 Diag(R.getNameLoc(), diagnostic) << Name;
2127 return true;
2128}
2129
2130/// In Microsoft mode, if we are inside a template class whose parent class has
2131/// dependent base classes, and we can't resolve an unqualified identifier, then
2132/// assume the identifier is a member of a dependent base class. We can only
2133/// recover successfully in static methods, instance methods, and other contexts
2134/// where 'this' is available. This doesn't precisely match MSVC's
2135/// instantiation model, but it's close enough.
2136static Expr *
2137recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context,
2138 DeclarationNameInfo &NameInfo,
2139 SourceLocation TemplateKWLoc,
2140 const TemplateArgumentListInfo *TemplateArgs) {
2141 // Only try to recover from lookup into dependent bases in static methods or
2142 // contexts where 'this' is available.
2143 QualType ThisType = S.getCurrentThisType();
2144 const CXXRecordDecl *RD = nullptr;
2145 if (!ThisType.isNull())
2146 RD = ThisType->getPointeeType()->getAsCXXRecordDecl();
2147 else if (auto *MD = dyn_cast<CXXMethodDecl>(S.CurContext))
2148 RD = MD->getParent();
2149 if (!RD || !RD->hasAnyDependentBases())
2150 return nullptr;
2151
2152 // Diagnose this as unqualified lookup into a dependent base class. If 'this'
2153 // is available, suggest inserting 'this->' as a fixit.
2154 SourceLocation Loc = NameInfo.getLoc();
2155 auto DB = S.Diag(Loc, diag::ext_undeclared_unqual_id_with_dependent_base);
2156 DB << NameInfo.getName() << RD;
2157
2158 if (!ThisType.isNull()) {
2159 DB << FixItHint::CreateInsertion(Loc, "this->");
2160 return CXXDependentScopeMemberExpr::Create(
2161 Context, /*This=*/nullptr, ThisType, /*IsArrow=*/true,
2162 /*Op=*/SourceLocation(), NestedNameSpecifierLoc(), TemplateKWLoc,
2163 /*FirstQualifierInScope=*/nullptr, NameInfo, TemplateArgs);
2164 }
2165
2166 // Synthesize a fake NNS that points to the derived class. This will
2167 // perform name lookup during template instantiation.
2168 CXXScopeSpec SS;
2169 auto *NNS =
2170 NestedNameSpecifier::Create(Context, nullptr, true, RD->getTypeForDecl());
2171 SS.MakeTrivial(Context, NNS, SourceRange(Loc, Loc));
2172 return DependentScopeDeclRefExpr::Create(
2173 Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
2174 TemplateArgs);
2175}
2176
2177ExprResult
2178Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
2179 SourceLocation TemplateKWLoc, UnqualifiedId &Id,
2180 bool HasTrailingLParen, bool IsAddressOfOperand,
2181 CorrectionCandidateCallback *CCC,
2182 bool IsInlineAsmIdentifier, Token *KeywordReplacement) {
2183 assert(!(IsAddressOfOperand && HasTrailingLParen) &&
2184 "cannot be direct & operand and have a trailing lparen");
2185 if (SS.isInvalid())
2186 return ExprError();
2187
2188 TemplateArgumentListInfo TemplateArgsBuffer;
2189
2190 // Decompose the UnqualifiedId into the following data.
2191 DeclarationNameInfo NameInfo;
2192 const TemplateArgumentListInfo *TemplateArgs;
2193 DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs);
2194
2195 DeclarationName Name = NameInfo.getName();
2196 IdentifierInfo *II = Name.getAsIdentifierInfo();
2197 SourceLocation NameLoc = NameInfo.getLoc();
2198
2199 if (II && II->isEditorPlaceholder()) {
2200 // FIXME: When typed placeholders are supported we can create a typed
2201 // placeholder expression node.
2202 return ExprError();
2203 }
2204
2205 // C++ [temp.dep.expr]p3:
2206 // An id-expression is type-dependent if it contains:
2207 // -- an identifier that was declared with a dependent type,
2208 // (note: handled after lookup)
2209 // -- a template-id that is dependent,
2210 // (note: handled in BuildTemplateIdExpr)
2211 // -- a conversion-function-id that specifies a dependent type,
2212 // -- a nested-name-specifier that contains a class-name that
2213 // names a dependent type.
2214 // Determine whether this is a member of an unknown specialization;
2215 // we need to handle these differently.
2216 bool DependentID = false;
2217 if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName &&
2218 Name.getCXXNameType()->isDependentType()) {
2219 DependentID = true;
2220 } else if (SS.isSet()) {
2221 if (DeclContext *DC = computeDeclContext(SS, false)) {
2222 if (RequireCompleteDeclContext(SS, DC))
2223 return ExprError();
2224 } else {
2225 DependentID = true;
2226 }
2227 }
2228
2229 if (DependentID)
2230 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2231 IsAddressOfOperand, TemplateArgs);
2232
2233 // Perform the required lookup.
2234 LookupResult R(*this, NameInfo,
2235 (Id.getKind() == UnqualifiedIdKind::IK_ImplicitSelfParam)
2236 ? LookupObjCImplicitSelfParam
2237 : LookupOrdinaryName);
2238 if (TemplateKWLoc.isValid() || TemplateArgs) {
2239 // Lookup the template name again to correctly establish the context in
2240 // which it was found. This is really unfortunate as we already did the
2241 // lookup to determine that it was a template name in the first place. If
2242 // this becomes a performance hit, we can work harder to preserve those
2243 // results until we get here but it's likely not worth it.
2244 bool MemberOfUnknownSpecialization;
2245 AssumedTemplateKind AssumedTemplate;
2246 if (LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false,
2247 MemberOfUnknownSpecialization, TemplateKWLoc,
2248 &AssumedTemplate))
2249 return ExprError();
2250
2251 if (MemberOfUnknownSpecialization ||
2252 (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation))
2253 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2254 IsAddressOfOperand, TemplateArgs);
2255 } else {
2256 bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl();
2257 LookupParsedName(R, S, &SS, !IvarLookupFollowUp);
2258
2259 // If the result might be in a dependent base class, this is a dependent
2260 // id-expression.
2261 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2262 return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
2263 IsAddressOfOperand, TemplateArgs);
2264
2265 // If this reference is in an Objective-C method, then we need to do
2266 // some special Objective-C lookup, too.
2267 if (IvarLookupFollowUp) {
2268 ExprResult E(LookupInObjCMethod(R, S, II, true));
2269 if (E.isInvalid())
2270 return ExprError();
2271
2272 if (Expr *Ex = E.getAs<Expr>())
2273 return Ex;
2274 }
2275 }
2276
2277 if (R.isAmbiguous())
2278 return ExprError();
2279
2280 // This could be an implicitly declared function reference (legal in C90,
2281 // extension in C99, forbidden in C++).
2282 if (R.empty() && HasTrailingLParen && II && !getLangOpts().CPlusPlus) {
2283 NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S);
2284 if (D) R.addDecl(D);
2285 }
2286
2287 // Determine whether this name might be a candidate for
2288 // argument-dependent lookup.
2289 bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen);
2290
2291 if (R.empty() && !ADL) {
2292 if (SS.isEmpty() && getLangOpts().MSVCCompat) {
2293 if (Expr *E = recoverFromMSUnqualifiedLookup(*this, Context, NameInfo,
2294 TemplateKWLoc, TemplateArgs))
2295 return E;
2296 }
2297
2298 // Don't diagnose an empty lookup for inline assembly.
2299 if (IsInlineAsmIdentifier)
2300 return ExprError();
2301
2302 // If this name wasn't predeclared and if this is not a function
2303 // call, diagnose the problem.
2304 TypoExpr *TE = nullptr;
2305 DefaultFilterCCC DefaultValidator(II, SS.isValid() ? SS.getScopeRep()
2306 : nullptr);
2307 DefaultValidator.IsAddressOfOperand = IsAddressOfOperand;
2308 assert((!CCC || CCC->IsAddressOfOperand == IsAddressOfOperand) &&
2309 "Typo correction callback misconfigured");
2310 if (CCC) {
2311 // Make sure the callback knows what the typo being diagnosed is.
2312 CCC->setTypoName(II);
2313 if (SS.isValid())
2314 CCC->setTypoNNS(SS.getScopeRep());
2315 }
2316 // FIXME: DiagnoseEmptyLookup produces bad diagnostics if we're looking for
2317 // a template name, but we happen to have always already looked up the name
2318 // before we get here if it must be a template name.
2319 if (DiagnoseEmptyLookup(S, SS, R, CCC ? *CCC : DefaultValidator, nullptr,
2320 None, &TE)) {
2321 if (TE && KeywordReplacement) {
2322 auto &State = getTypoExprState(TE);
2323 auto BestTC = State.Consumer->getNextCorrection();
2324 if (BestTC.isKeyword()) {
2325 auto *II = BestTC.getCorrectionAsIdentifierInfo();
2326 if (State.DiagHandler)
2327 State.DiagHandler(BestTC);
2328 KeywordReplacement->startToken();
2329 KeywordReplacement->setKind(II->getTokenID());
2330 KeywordReplacement->setIdentifierInfo(II);
2331 KeywordReplacement->setLocation(BestTC.getCorrectionRange().getBegin());
2332 // Clean up the state associated with the TypoExpr, since it has
2333 // now been diagnosed (without a call to CorrectDelayedTyposInExpr).
2334 clearDelayedTypo(TE);
2335 // Signal that a correction to a keyword was performed by returning a
2336 // valid-but-null ExprResult.
2337 return (Expr*)nullptr;
2338 }
2339 State.Consumer->resetCorrectionStream();
2340 }
2341 return TE ? TE : ExprError();
2342 }
2343
2344 assert(!R.empty() &&
2345 "DiagnoseEmptyLookup returned false but added no results");
2346
2347 // If we found an Objective-C instance variable, let
2348 // LookupInObjCMethod build the appropriate expression to
2349 // reference the ivar.
2350 if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) {
2351 R.clear();
2352 ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier()));
2353 // In a hopelessly buggy code, Objective-C instance variable
2354 // lookup fails and no expression will be built to reference it.
2355 if (!E.isInvalid() && !E.get())
2356 return ExprError();
2357 return E;
2358 }
2359 }
2360
2361 // This is guaranteed from this point on.
2362 assert(!R.empty() || ADL);
2363
2364 // Check whether this might be a C++ implicit instance member access.
2365 // C++ [class.mfct.non-static]p3:
2366 // When an id-expression that is not part of a class member access
2367 // syntax and not used to form a pointer to member is used in the
2368 // body of a non-static member function of class X, if name lookup
2369 // resolves the name in the id-expression to a non-static non-type
2370 // member of some class C, the id-expression is transformed into a
2371 // class member access expression using (*this) as the
2372 // postfix-expression to the left of the . operator.
2373 //
2374 // But we don't actually need to do this for '&' operands if R
2375 // resolved to a function or overloaded function set, because the
2376 // expression is ill-formed if it actually works out to be a
2377 // non-static member function:
2378 //
2379 // C++ [expr.ref]p4:
2380 // Otherwise, if E1.E2 refers to a non-static member function. . .
2381 // [t]he expression can be used only as the left-hand operand of a
2382 // member function call.
2383 //
2384 // There are other safeguards against such uses, but it's important
2385 // to get this right here so that we don't end up making a
2386 // spuriously dependent expression if we're inside a dependent
2387 // instance method.
2388 if (!R.empty() && (*R.begin())->isCXXClassMember()) {
2389 bool MightBeImplicitMember;
2390 if (!IsAddressOfOperand)
2391 MightBeImplicitMember = true;
2392 else if (!SS.isEmpty())
2393 MightBeImplicitMember = false;
2394 else if (R.isOverloadedResult())
2395 MightBeImplicitMember = false;
2396 else if (R.isUnresolvableResult())
2397 MightBeImplicitMember = true;
2398 else
2399 MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) ||
2400 isa<IndirectFieldDecl>(R.getFoundDecl()) ||
2401 isa<MSPropertyDecl>(R.getFoundDecl());
2402
2403 if (MightBeImplicitMember)
2404 return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc,
2405 R, TemplateArgs, S);
2406 }
2407
2408 if (TemplateArgs || TemplateKWLoc.isValid()) {
2409
2410 // In C++1y, if this is a variable template id, then check it
2411 // in BuildTemplateIdExpr().
2412 // The single lookup result must be a variable template declaration.
2413 if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId && Id.TemplateId &&
2414 Id.TemplateId->Kind == TNK_Var_template) {
2415 assert(R.getAsSingle<VarTemplateDecl>() &&
2416 "There should only be one declaration found.");
2417 }
2418
2419 return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs);
2420 }
2421
2422 return BuildDeclarationNameExpr(SS, R, ADL);
2423}
2424
2425/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified
2426/// declaration name, generally during template instantiation.
2427/// There's a large number of things which don't need to be done along
2428/// this path.
2429ExprResult Sema::BuildQualifiedDeclarationNameExpr(
2430 CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo,
2431 bool IsAddressOfOperand, const Scope *S, TypeSourceInfo **RecoveryTSI) {
2432 DeclContext *DC = computeDeclContext(SS, false);
2433 if (!DC)
2434 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2435 NameInfo, /*TemplateArgs=*/nullptr);
2436
2437 if (RequireCompleteDeclContext(SS, DC))
2438 return ExprError();
2439
2440 LookupResult R(*this, NameInfo, LookupOrdinaryName);
2441 LookupQualifiedName(R, DC);
2442
2443 if (R.isAmbiguous())
2444 return ExprError();
2445
2446 if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
2447 return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
2448 NameInfo, /*TemplateArgs=*/nullptr);
2449
2450 if (R.empty()) {
2451 Diag(NameInfo.getLoc(), diag::err_no_member)
2452 << NameInfo.getName() << DC << SS.getRange();
2453 return ExprError();
2454 }
2455
2456 if (const TypeDecl *TD = R.getAsSingle<TypeDecl>()) {
2457 // Diagnose a missing typename if this resolved unambiguously to a type in
2458 // a dependent context. If we can recover with a type, downgrade this to
2459 // a warning in Microsoft compatibility mode.
2460 unsigned DiagID = diag::err_typename_missing;
2461 if (RecoveryTSI && getLangOpts().MSVCCompat)
2462 DiagID = diag::ext_typename_missing;
2463 SourceLocation Loc = SS.getBeginLoc();
2464 auto D = Diag(Loc, DiagID);
2465 D << SS.getScopeRep() << NameInfo.getName().getAsString()
2466 << SourceRange(Loc, NameInfo.getEndLoc());
2467
2468 // Don't recover if the caller isn't expecting us to or if we're in a SFINAE
2469 // context.
2470 if (!RecoveryTSI)
2471 return ExprError();
2472
2473 // Only issue the fixit if we're prepared to recover.
2474 D << FixItHint::CreateInsertion(Loc, "typename ");
2475
2476 // Recover by pretending this was an elaborated type.
2477 QualType Ty = Context.getTypeDeclType(TD);
2478 TypeLocBuilder TLB;
2479 TLB.pushTypeSpec(Ty).setNameLoc(NameInfo.getLoc());
2480
2481 QualType ET = getElaboratedType(ETK_None, SS, Ty);
2482 ElaboratedTypeLoc QTL = TLB.push<ElaboratedTypeLoc>(ET);
2483 QTL.setElaboratedKeywordLoc(SourceLocation());
2484 QTL.setQualifierLoc(SS.getWithLocInContext(Context));
2485
2486 *RecoveryTSI = TLB.getTypeSourceInfo(Context, ET);
2487
2488 return ExprEmpty();
2489 }
2490
2491 // Defend against this resolving to an implicit member access. We usually
2492 // won't get here if this might be a legitimate a class member (we end up in
2493 // BuildMemberReferenceExpr instead), but this can be valid if we're forming
2494 // a pointer-to-member or in an unevaluated context in C++11.
2495 if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand)
2496 return BuildPossibleImplicitMemberExpr(SS,
2497 /*TemplateKWLoc=*/SourceLocation(),
2498 R, /*TemplateArgs=*/nullptr, S);
2499
2500 return BuildDeclarationNameExpr(SS, R, /* ADL */ false);
2501}
2502
2503/// LookupInObjCMethod - The parser has read a name in, and Sema has
2504/// detected that we're currently inside an ObjC method. Perform some
2505/// additional lookup.
2506///
2507/// Ideally, most of this would be done by lookup, but there's
2508/// actually quite a lot of extra work involved.
2509///
2510/// Returns a null sentinel to indicate trivial success.
2511ExprResult
2512Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
2513 IdentifierInfo *II, bool AllowBuiltinCreation) {
2514 SourceLocation Loc = Lookup.getNameLoc();
2515 ObjCMethodDecl *CurMethod = getCurMethodDecl();
2516
2517 // Check for error condition which is already reported.
2518 if (!CurMethod)
2519 return ExprError();
2520
2521 // There are two cases to handle here. 1) scoped lookup could have failed,
2522 // in which case we should look for an ivar. 2) scoped lookup could have
2523 // found a decl, but that decl is outside the current instance method (i.e.
2524 // a global variable). In these two cases, we do a lookup for an ivar with
2525 // this name, if the lookup sucedes, we replace it our current decl.
2526
2527 // If we're in a class method, we don't normally want to look for
2528 // ivars. But if we don't find anything else, and there's an
2529 // ivar, that's an error.
2530 bool IsClassMethod = CurMethod->isClassMethod();
2531
2532 bool LookForIvars;
2533 if (Lookup.empty())
2534 LookForIvars = true;
2535 else if (IsClassMethod)
2536 LookForIvars = false;
2537 else
2538 LookForIvars = (Lookup.isSingleResult() &&
2539 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod());
2540 ObjCInterfaceDecl *IFace = nullptr;
2541 if (LookForIvars) {
2542 IFace = CurMethod->getClassInterface();
2543 ObjCInterfaceDecl *ClassDeclared;
2544 ObjCIvarDecl *IV = nullptr;
2545 if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) {
2546 // Diagnose using an ivar in a class method.
2547 if (IsClassMethod)
2548 return ExprError(Diag(Loc, diag::err_ivar_use_in_class_method)
2549 << IV->getDeclName());
2550
2551 // If we're referencing an invalid decl, just return this as a silent
2552 // error node. The error diagnostic was already emitted on the decl.
2553 if (IV->isInvalidDecl())
2554 return ExprError();
2555
2556 // Check if referencing a field with __attribute__((deprecated)).
2557 if (DiagnoseUseOfDecl(IV, Loc))
2558 return ExprError();
2559
2560 // Diagnose the use of an ivar outside of the declaring class.
2561 if (IV->getAccessControl() == ObjCIvarDecl::Private &&
2562 !declaresSameEntity(ClassDeclared, IFace) &&
2563 !getLangOpts().DebuggerSupport)
2564 Diag(Loc, diag::err_private_ivar_access) << IV->getDeclName();
2565
2566 // FIXME: This should use a new expr for a direct reference, don't
2567 // turn this into Self->ivar, just return a BareIVarExpr or something.
2568 IdentifierInfo &II = Context.Idents.get("self");
2569 UnqualifiedId SelfName;
2570 SelfName.setIdentifier(&II, SourceLocation());
2571 SelfName.setKind(UnqualifiedIdKind::IK_ImplicitSelfParam);
2572 CXXScopeSpec SelfScopeSpec;
2573 SourceLocation TemplateKWLoc;
2574 ExprResult SelfExpr =
2575 ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc, SelfName,
2576 /*HasTrailingLParen=*/false,
2577 /*IsAddressOfOperand=*/false);
2578 if (SelfExpr.isInvalid())
2579 return ExprError();
2580
2581 SelfExpr = DefaultLvalueConversion(SelfExpr.get());
2582 if (SelfExpr.isInvalid())
2583 return ExprError();
2584
2585 MarkAnyDeclReferenced(Loc, IV, true);
2586
2587 ObjCMethodFamily MF = CurMethod->getMethodFamily();
2588 if (MF != OMF_init && MF != OMF_dealloc && MF != OMF_finalize &&
2589 !IvarBacksCurrentMethodAccessor(IFace, CurMethod, IV))
2590 Diag(Loc, diag::warn_direct_ivar_access) << IV->getDeclName();
2591
2592 ObjCIvarRefExpr *Result = new (Context)
2593 ObjCIvarRefExpr(IV, IV->getUsageType(SelfExpr.get()->getType()), Loc,
2594 IV->getLocation(), SelfExpr.get(), true, true);
2595
2596 if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
2597 if (!isUnevaluatedContext() &&
2598 !Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
2599 getCurFunction()->recordUseOfWeak(Result);
2600 }
2601 if (getLangOpts().ObjCAutoRefCount)
2602 if (const BlockDecl *BD = CurContext->getInnermostBlockDecl())
2603 ImplicitlyRetainedSelfLocs.push_back({Loc, BD});
2604
2605 return Result;
2606 }
2607 } else if (CurMethod->isInstanceMethod()) {
2608 // We should warn if a local variable hides an ivar.
2609 if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) {
2610 ObjCInterfaceDecl *ClassDeclared;
2611 if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) {
2612 if (IV->getAccessControl() != ObjCIvarDecl::Private ||
2613 declaresSameEntity(IFace, ClassDeclared))
2614 Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName();
2615 }
2616 }
2617 } else if (Lookup.isSingleResult() &&
2618 Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) {
2619 // If accessing a stand-alone ivar in a class method, this is an error.
2620 if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl()))
2621 return ExprError(Diag(Loc, diag::err_ivar_use_in_class_method)
2622 << IV->getDeclName());
2623 }
2624
2625 if (Lookup.empty() && II && AllowBuiltinCreation) {
2626 // FIXME. Consolidate this with similar code in LookupName.
2627 if (unsigned BuiltinID = II->getBuiltinID()) {
2628 if (!(getLangOpts().CPlusPlus &&
2629 Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) {
2630 NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID,
2631 S, Lookup.isForRedeclaration(),
2632 Lookup.getNameLoc());
2633 if (D) Lookup.addDecl(D);
2634 }
2635 }
2636 }
2637 // Sentinel value saying that we didn't do anything special.
2638 return ExprResult((Expr *)nullptr);
2639}
2640
2641/// Cast a base object to a member's actual type.
2642///
2643/// Logically this happens in three phases:
2644///
2645/// * First we cast from the base type to the naming class.
2646/// The naming class is the class into which we were looking
2647/// when we found the member; it's the qualifier type if a
2648/// qualifier was provided, and otherwise it's the base type.
2649///
2650/// * Next we cast from the naming class to the declaring class.
2651/// If the member we found was brought into a class's scope by
2652/// a using declaration, this is that class; otherwise it's
2653/// the class declaring the member.
2654///
2655/// * Finally we cast from the declaring class to the "true"
2656/// declaring class of the member. This conversion does not
2657/// obey access control.
2658ExprResult
2659Sema::PerformObjectMemberConversion(Expr *From,
2660 NestedNameSpecifier *Qualifier,
2661 NamedDecl *FoundDecl,
2662 NamedDecl *Member) {
2663 CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext());
2664 if (!RD)
2665 return From;
2666
2667 QualType DestRecordType;
2668 QualType DestType;
2669 QualType FromRecordType;
2670 QualType FromType = From->getType();
2671 bool PointerConversions = false;
2672 if (isa<FieldDecl>(Member)) {
2673 DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD));
2674 auto FromPtrType = FromType->getAs<PointerType>();
2675 DestRecordType = Context.getAddrSpaceQualType(
2676 DestRecordType, FromPtrType
2677 ? FromType->getPointeeType().getAddressSpace()
2678 : FromType.getAddressSpace());
2679
2680 if (FromPtrType) {
2681 DestType = Context.getPointerType(DestRecordType,
2682 FromPtrType->isCHERICapability()
2683 ? ASTContext::PIK_Capability
2684 : ASTContext::PIK_Integer);
2685 FromRecordType = FromPtrType->getPointeeType();
2686 PointerConversions = true;
2687 } else {
2688 DestType = DestRecordType;
2689 FromRecordType = FromType;
2690 }
2691 } else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) {
2692 if (Method->isStatic())
2693 return From;
2694
2695 DestType = Method->getThisType();
2696 DestRecordType = DestType->getPointeeType();
2697
2698 if (FromType->getAs<PointerType>()) {
2699 FromRecordType = FromType->getPointeeType();
2700 PointerConversions = true;
2701 } else {
2702 FromRecordType = FromType;
2703 DestType = DestRecordType;
2704 }
2705 } else {
2706 // No conversion necessary.
2707 return From;
2708 }
2709
2710 if (DestType->isDependentType() || FromType->isDependentType())
2711 return From;
2712
2713 // If the unqualified types are the same, no conversion is necessary.
2714 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
2715 return From;
2716
2717 SourceRange FromRange = From->getSourceRange();
2718 SourceLocation FromLoc = FromRange.getBegin();
2719
2720 ExprValueKind VK = From->getValueKind();
2721
2722 // C++ [class.member.lookup]p8:
2723 // [...] Ambiguities can often be resolved by qualifying a name with its
2724 // class name.
2725 //
2726 // If the member was a qualified name and the qualified referred to a
2727 // specific base subobject type, we'll cast to that intermediate type
2728 // first and then to the object in which the member is declared. That allows
2729 // one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as:
2730 //
2731 // class Base { public: int x; };
2732 // class Derived1 : public Base { };
2733 // class Derived2 : public Base { };
2734 // class VeryDerived : public Derived1, public Derived2 { void f(); };
2735 //
2736 // void VeryDerived::f() {
2737 // x = 17; // error: ambiguous base subobjects
2738 // Derived1::x = 17; // okay, pick the Base subobject of Derived1
2739 // }
2740 if (Qualifier && Qualifier->getAsType()) {
2741 QualType QType = QualType(Qualifier->getAsType(), 0);
2742 assert(QType->isRecordType() && "lookup done with non-record type");
2743
2744 QualType QRecordType = QualType(QType->getAs<RecordType>(), 0);
2745
2746 // In C++98, the qualifier type doesn't actually have to be a base
2747 // type of the object type, in which case we just ignore it.
2748 // Otherwise build the appropriate casts.
2749 if (IsDerivedFrom(FromLoc, FromRecordType, QRecordType)) {
2750 CXXCastPath BasePath;
2751 if (CheckDerivedToBaseConversion(FromRecordType, QRecordType,
2752 FromLoc, FromRange, &BasePath))
2753 return ExprError();
2754
2755 if (PointerConversions)
2756 QType = Context.getPointerType(QType,
2757 FromType->isCHERICapabilityType(Context)
2758 ? ASTContext::PIK_Capability
2759 : ASTContext::PIK_Integer);
2760 From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase,
2761 VK, &BasePath).get();
2762
2763 FromType = QType;
2764 FromRecordType = QRecordType;
2765
2766 // If the qualifier type was the same as the destination type,
2767 // we're done.
2768 if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
2769 return From;
2770 }
2771 }
2772
2773 bool IgnoreAccess = false;
2774
2775 // If we actually found the member through a using declaration, cast
2776 // down to the using declaration's type.
2777 //
2778 // Pointer equality is fine here because only one declaration of a
2779 // class ever has member declarations.
2780 if (FoundDecl->getDeclContext() != Member->getDeclContext()) {
2781 assert(isa<UsingShadowDecl>(FoundDecl));
2782 QualType URecordType = Context.getTypeDeclType(
2783 cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
2784
2785 // We only need to do this if the naming-class to declaring-class
2786 // conversion is non-trivial.
2787 if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) {
2788 assert(IsDerivedFrom(FromLoc, FromRecordType, URecordType));
2789 CXXCastPath BasePath;
2790 if (CheckDerivedToBaseConversion(FromRecordType, URecordType,
2791 FromLoc, FromRange, &BasePath))
2792 return ExprError();
2793
2794 QualType UType = URecordType;
2795 if (PointerConversions)
2796 UType = Context.getPointerType(UType,
2797 FromType->isCHERICapabilityType(Context)
2798 ? ASTContext::PIK_Capability
2799 : ASTContext::PIK_Integer);
2800 From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase,
2801 VK, &BasePath).get();
2802 FromType = UType;
2803 FromRecordType = URecordType;
2804 }
2805
2806 // We don't do access control for the conversion from the
2807 // declaring class to the true declaring class.
2808 IgnoreAccess = true;
2809 }
2810
2811 CXXCastPath BasePath;
2812 if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType,
2813 FromLoc, FromRange, &BasePath,
2814 IgnoreAccess))
2815 return ExprError();
2816
2817 return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase,
2818 VK, &BasePath);
2819}
2820
2821bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS,
2822 const LookupResult &R,
2823 bool HasTrailingLParen) {
2824 // Only when used directly as the postfix-expression of a call.
2825 if (!HasTrailingLParen)
2826 return false;
2827
2828 // Never if a scope specifier was provided.
2829 if (SS.isSet())
2830 return false;
2831
2832 // Only in C++ or ObjC++.
2833 if (!getLangOpts().CPlusPlus)
2834 return false;
2835
2836 // Turn off ADL when we find certain kinds of declarations during
2837 // normal lookup:
2838 for (NamedDecl *D : R) {
2839 // C++0x [basic.lookup.argdep]p3:
2840 // -- a declaration of a class member
2841 // Since using decls preserve this property, we check this on the
2842 // original decl.
2843 if (D->isCXXClassMember())
2844 return false;
2845
2846 // C++0x [basic.lookup.argdep]p3:
2847 // -- a block-scope function declaration that is not a
2848 // using-declaration
2849 // NOTE: we also trigger this for function templates (in fact, we
2850 // don't check the decl type at all, since all other decl types
2851 // turn off ADL anyway).
2852 if (isa<UsingShadowDecl>(D))
2853 D = cast<UsingShadowDecl>(D)->getTargetDecl();
2854 else if (D->getLexicalDeclContext()->isFunctionOrMethod())
2855 return false;
2856
2857 // C++0x [basic.lookup.argdep]p3:
2858 // -- a declaration that is neither a function or a function
2859 // template
2860 // And also for builtin functions.
2861 if (isa<FunctionDecl>(D)) {
2862 FunctionDecl *FDecl = cast<FunctionDecl>(D);
2863
2864 // But also builtin functions.
2865 if (FDecl->getBuiltinID() && FDecl->isImplicit())
2866 return false;
2867 } else if (!isa<FunctionTemplateDecl>(D))
2868 return false;
2869 }
2870
2871 return true;
2872}
2873
2874
2875/// Diagnoses obvious problems with the use of the given declaration
2876/// as an expression. This is only actually called for lookups that
2877/// were not overloaded, and it doesn't promise that the declaration
2878/// will in fact be used.
2879static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) {
2880 if (D->isInvalidDecl())
2881 return true;
2882
2883 if (isa<TypedefNameDecl>(D)) {
2884 S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName();
2885 return true;
2886 }
2887
2888 if (isa<ObjCInterfaceDecl>(D)) {
2889 S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName();
2890 return true;
2891 }
2892
2893 if (isa<NamespaceDecl>(D)) {
2894 S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName();
2895 return true;
2896 }
2897
2898 return false;
2899}
2900
2901// Certain multiversion types should be treated as overloaded even when there is
2902// only one result.
2903static bool ShouldLookupResultBeMultiVersionOverload(const LookupResult &R) {
2904 assert(R.isSingleResult() && "Expected only a single result");
2905 const auto *FD = dyn_cast<FunctionDecl>(R.getFoundDecl());
2906 return FD &&
2907 (FD->isCPUDispatchMultiVersion() || FD->isCPUSpecificMultiVersion());
2908}
2909
2910ExprResult Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
2911 LookupResult &R, bool NeedsADL,
2912 bool AcceptInvalidDecl) {
2913 // If this is a single, fully-resolved result and we don't need ADL,
2914 // just build an ordinary singleton decl ref.
2915 if (!NeedsADL && R.isSingleResult() &&
2916 !R.getAsSingle<FunctionTemplateDecl>() &&
2917 !ShouldLookupResultBeMultiVersionOverload(R))
2918 return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), R.getFoundDecl(),
2919 R.getRepresentativeDecl(), nullptr,
2920 AcceptInvalidDecl);
2921
2922 // We only need to check the declaration if there's exactly one
2923 // result, because in the overloaded case the results can only be
2924 // functions and function templates.
2925 if (R.isSingleResult() && !ShouldLookupResultBeMultiVersionOverload(R) &&
2926 CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl()))
2927 return ExprError();
2928
2929 // Otherwise, just build an unresolved lookup expression. Suppress
2930 // any lookup-related diagnostics; we'll hash these out later, when
2931 // we've picked a target.
2932 R.suppressDiagnostics();
2933
2934 UnresolvedLookupExpr *ULE
2935 = UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
2936 SS.getWithLocInContext(Context),
2937 R.getLookupNameInfo(),
2938 NeedsADL, R.isOverloadedResult(),
2939 R.begin(), R.end());
2940
2941 return ULE;
2942}
2943
2944static void
2945diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
2946 ValueDecl *var, DeclContext *DC);
2947
2948/// Complete semantic analysis for a reference to the given declaration.
2949ExprResult Sema::BuildDeclarationNameExpr(
2950 const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
2951 NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs,
2952 bool AcceptInvalidDecl) {
2953 assert(D && "Cannot refer to a NULL declaration");
2954 assert(!isa<FunctionTemplateDecl>(D) &&
2955 "Cannot refer unambiguously to a function template");
2956
2957 SourceLocation Loc = NameInfo.getLoc();
2958 if (CheckDeclInExpr(*this, Loc, D))
2959 return ExprError();
2960
2961 if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) {
2962 // Specifically diagnose references to class templates that are missing
2963 // a template argument list.
2964 diagnoseMissingTemplateArguments(TemplateName(Template), Loc);
2965 return ExprError();
2966 }
2967
2968 // Make sure that we're referring to a value.
2969 ValueDecl *VD = dyn_cast<ValueDecl>(D);
2970 if (!VD) {
2971 Diag(Loc, diag::err_ref_non_value)
2972 << D << SS.getRange();
2973 Diag(D->getLocation(), diag::note_declared_at);
2974 return ExprError();
2975 }
2976
2977 // Check whether this declaration can be used. Note that we suppress
2978 // this check when we're going to perform argument-dependent lookup
2979 // on this function name, because this might not be the function
2980 // that overload resolution actually selects.
2981 if (DiagnoseUseOfDecl(VD, Loc))
2982 return ExprError();
2983
2984 // Only create DeclRefExpr's for valid Decl's.
2985 if (VD->isInvalidDecl() && !AcceptInvalidDecl)
2986 return ExprError();
2987
2988 // Handle members of anonymous structs and unions. If we got here,
2989 // and the reference is to a class member indirect field, then this
2990 // must be the subject of a pointer-to-member expression.
2991 if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD))
2992 if (!indirectField->isCXXClassMember())
2993 return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(),
2994 indirectField);
2995
2996 {
2997 QualType type = VD->getType();
2998 if (type.isNull())
2999 return ExprError();
3000 if (auto *FPT = type->getAs<FunctionProtoType>()) {
3001 // C++ [except.spec]p17:
3002 // An exception-specification is considered to be needed when:
3003 // - in an expression, the function is the unique lookup result or
3004 // the selected member of a set of overloaded functions.
3005 ResolveExceptionSpec(Loc, FPT);
3006 type = VD->getType();
3007 }
3008 ExprValueKind valueKind = VK_RValue;
3009
3010 switch (D->getKind()) {
3011 // Ignore all the non-ValueDecl kinds.
3012#define ABSTRACT_DECL(kind)
3013#define VALUE(type, base)
3014#define DECL(type, base) \
3015 case Decl::type:
3016#include "clang/AST/DeclNodes.inc"
3017 llvm_unreachable("invalid value decl kind");
3018
3019 // These shouldn't make it here.
3020 case Decl::ObjCAtDefsField:
3021 llvm_unreachable("forming non-member reference to ivar?");
3022
3023 // Enum constants are always r-values and never references.
3024 // Unresolved using declarations are dependent.
3025 case Decl::EnumConstant:
3026 case Decl::UnresolvedUsingValue:
3027 case Decl::OMPDeclareReduction:
3028 case Decl::OMPDeclareMapper:
3029 valueKind = VK_RValue;
3030 break;
3031
3032 // Fields and indirect fields that got here must be for
3033 // pointer-to-member expressions; we just call them l-values for
3034 // internal consistency, because this subexpression doesn't really
3035 // exist in the high-level semantics.
3036 case Decl::Field:
3037 case Decl::IndirectField:
3038 case Decl::ObjCIvar:
3039 assert(getLangOpts().CPlusPlus &&
3040 "building reference to field in C?");
3041
3042 // These can't have reference type in well-formed programs, but
3043 // for internal consistency we do this anyway.
3044 type = type.getNonReferenceType();
3045 valueKind = VK_LValue;
3046 break;
3047
3048 // Non-type template parameters are either l-values or r-values
3049 // depending on the type.
3050 case Decl::NonTypeTemplateParm: {
3051 if (const ReferenceType *reftype = type->getAs<ReferenceType>()) {
3052 type = reftype->getPointeeType();
3053 valueKind = VK_LValue; // even if the parameter is an r-value reference
3054 break;
3055 }
3056
3057 // For non-references, we need to strip qualifiers just in case
3058 // the template parameter was declared as 'const int' or whatever.
3059 valueKind = VK_RValue;
3060 type = type.getUnqualifiedType();
3061 break;
3062 }
3063
3064 case Decl::Var:
3065 case Decl::VarTemplateSpecialization:
3066 case Decl::VarTemplatePartialSpecialization:
3067 case Decl::Decomposition:
3068 case Decl::OMPCapturedExpr:
3069 // In C, "extern void blah;" is valid and is an r-value.
3070 if (!getLangOpts().CPlusPlus &&
3071 !type.hasQualifiers() &&
3072 type->isVoidType()) {
3073 valueKind = VK_RValue;
3074 break;
3075 }
3076 LLVM_FALLTHROUGH;
3077
3078 case Decl::ImplicitParam:
3079 case Decl::ParmVar: {
3080 // These are always l-values.
3081 valueKind = VK_LValue;
3082 type = type.getNonReferenceType();
3083
3084 // FIXME: Does the addition of const really only apply in
3085 // potentially-evaluated contexts? Since the variable isn't actually
3086 // captured in an unevaluated context, it seems that the answer is no.
3087 if (!isUnevaluatedContext()) {
3088 QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc);
3089 if (!CapturedType.isNull())
3090 type = CapturedType;
3091 }
3092
3093 break;
3094 }
3095
3096 case Decl::Binding: {
3097 // These are always lvalues.
3098 valueKind = VK_LValue;
3099 type = type.getNonReferenceType();
3100 // FIXME: Support lambda-capture of BindingDecls, once CWG actually
3101 // decides how that's supposed to work.
3102 auto *BD = cast<BindingDecl>(VD);
3103 if (BD->getDeclContext() != CurContext) {
3104 auto *DD = dyn_cast_or_null<VarDecl>(BD->getDecomposedDecl());
3105 if (DD && DD->hasLocalStorage())
3106 diagnoseUncapturableValueReference(*this, Loc, BD, CurContext);
3107 }
3108 break;
3109 }
3110
3111 case Decl::Function: {
3112 if (unsigned BID = cast<FunctionDecl>(VD)->getBuiltinID()) {
3113 if (!Context.BuiltinInfo.isPredefinedLibFunction(BID)) {
3114 type = Context.BuiltinFnTy;
3115 valueKind = VK_RValue;
3116 break;
3117 }
3118 }
3119
3120 const FunctionType *fty = type->castAs<FunctionType>();
3121
3122 // If we're referring to a function with an __unknown_anytype
3123 // result type, make the entire expression __unknown_anytype.
3124 if (fty->getReturnType() == Context.UnknownAnyTy) {
3125 type = Context.UnknownAnyTy;
3126 valueKind = VK_RValue;
3127 break;
3128 }
3129
3130 // Functions are l-values in C++.
3131 if (getLangOpts().CPlusPlus) {
3132 valueKind = VK_LValue;
3133 break;
3134 }
3135
3136 // C99 DR 316 says that, if a function type comes from a
3137 // function definition (without a prototype), that type is only
3138 // used for checking compatibility. Therefore, when referencing
3139 // the function, we pretend that we don't have the full function
3140 // type.
3141 if (!cast<FunctionDecl>(VD)->hasPrototype() &&
3142 isa<FunctionProtoType>(fty))
3143 type = Context.getFunctionNoProtoType(fty->getReturnType(),
3144 fty->getExtInfo());
3145
3146 // Functions are r-values in C.
3147 valueKind = VK_RValue;
3148 break;
3149 }
3150
3151 case Decl::CXXDeductionGuide:
3152 llvm_unreachable("building reference to deduction guide");
3153
3154 case Decl::MSProperty:
3155 valueKind = VK_LValue;
3156 break;
3157
3158 case Decl::CXXMethod:
3159 // If we're referring to a method with an __unknown_anytype
3160 // result type, make the entire expression __unknown_anytype.
3161 // This should only be possible with a type written directly.
3162 if (const FunctionProtoType *proto
3163 = dyn_cast<FunctionProtoType>(VD->getType()))
3164 if (proto->getReturnType() == Context.UnknownAnyTy) {
3165 type = Context.UnknownAnyTy;
3166 valueKind = VK_RValue;
3167 break;
3168 }
3169
3170 // C++ methods are l-values if static, r-values if non-static.
3171 if (cast<CXXMethodDecl>(VD)->isStatic()) {
3172 valueKind = VK_LValue;
3173 break;
3174 }
3175 LLVM_FALLTHROUGH;
3176
3177 case Decl::CXXConversion:
3178 case Decl::CXXDestructor:
3179 case Decl::CXXConstructor:
3180 valueKind = VK_RValue;
3181 break;
3182 }
3183
3184 return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS, FoundD,
3185 /*FIXME: TemplateKWLoc*/ SourceLocation(),
3186 TemplateArgs);
3187 }
3188}
3189
3190static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
3191 SmallString<32> &Target) {
3192 Target.resize(CharByteWidth * (Source.size() + 1));
3193 char *ResultPtr = &Target[0];
3194 const llvm::UTF8 *ErrorPtr;
3195 bool success =
3196 llvm::ConvertUTF8toWide(CharByteWidth, Source, ResultPtr, ErrorPtr);
3197 (void)success;
3198 assert(success);
3199 Target.resize(ResultPtr - &Target[0]);
3200}
3201
3202ExprResult Sema::BuildPredefinedExpr(SourceLocation Loc,
3203 PredefinedExpr::IdentKind IK) {
3204 // Pick the current block, lambda, captured statement or function.
3205 Decl *currentDecl = nullptr;
3206 if (const BlockScopeInfo *BSI = getCurBlock())
3207 currentDecl = BSI->TheDecl;
3208 else if (const LambdaScopeInfo *LSI = getCurLambda())
3209 currentDecl = LSI->CallOperator;
3210 else if (const CapturedRegionScopeInfo *CSI = getCurCapturedRegion())
3211 currentDecl = CSI->TheCapturedDecl;
3212 else
3213 currentDecl = getCurFunctionOrMethodDecl();
3214
3215 if (!currentDecl) {
3216 Diag(Loc, diag::ext_predef_outside_function);
3217 currentDecl = Context.getTranslationUnitDecl();
3218 }
3219
3220 QualType ResTy;
3221 StringLiteral *SL = nullptr;
3222 if (cast<DeclContext>(currentDecl)->isDependentContext())
3223 ResTy = Context.DependentTy;
3224 else {
3225 // Pre-defined identifiers are of type char[x], where x is the length of
3226 // the string.
3227 auto Str = PredefinedExpr::ComputeName(IK, currentDecl);
3228 unsigned Length = Str.length();
3229
3230 llvm::APInt LengthI(32, Length + 1);
3231 if (IK == PredefinedExpr::LFunction || IK == PredefinedExpr::LFuncSig) {
3232 ResTy =
3233 Context.adjustStringLiteralBaseType(Context.WideCharTy.withConst());
3234 SmallString<32> RawChars;
3235 ConvertUTF8ToWideString(Context.getTypeSizeInChars(ResTy).getQuantity(),
3236 Str, RawChars);
3237 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
3238 /*IndexTypeQuals*/ 0);
3239 SL = StringLiteral::Create(Context, RawChars, StringLiteral::Wide,
3240 /*Pascal*/ false, ResTy, Loc);
3241 } else {
3242 ResTy = Context.adjustStringLiteralBaseType(Context.CharTy.withConst());
3243 ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
3244 /*IndexTypeQuals*/ 0);
3245 SL = StringLiteral::Create(Context, Str, StringLiteral::Ascii,
3246 /*Pascal*/ false, ResTy, Loc);
3247 }
3248 }
3249
3250 return PredefinedExpr::Create(Context, Loc, ResTy, IK, SL);
3251}
3252
3253ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
3254 PredefinedExpr::IdentKind IK;
3255
3256 switch (Kind) {
3257 default: llvm_unreachable("Unknown simple primary expr!");
3258 case tok::kw___func__: IK = PredefinedExpr::Func; break; // [C99 6.4.2.2]
3259 case tok::kw___FUNCTION__: IK = PredefinedExpr::Function; break;
3260 case tok::kw___FUNCDNAME__: IK = PredefinedExpr::FuncDName; break; // [MS]
3261 case tok::kw___FUNCSIG__: IK = PredefinedExpr::FuncSig; break; // [MS]
3262 case tok::kw_L__FUNCTION__: IK = PredefinedExpr::LFunction; break; // [MS]
3263 case tok::kw_L__FUNCSIG__: IK = PredefinedExpr::LFuncSig; break; // [MS]
3264 case tok::kw___PRETTY_FUNCTION__: IK = PredefinedExpr::PrettyFunction; break;
3265 }
3266
3267 return BuildPredefinedExpr(Loc, IK);
3268}
3269
3270ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
3271 SmallString<16> CharBuffer;
3272 bool Invalid = false;
3273 StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid);
3274 if (Invalid)
3275 return ExprError();
3276
3277 CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(),
3278 PP, Tok.getKind());
3279 if (Literal.hadError())
3280 return ExprError();
3281
3282 QualType Ty;
3283 if (Literal.isWide())
3284 Ty = Context.WideCharTy; // L'x' -> wchar_t in C and C++.
3285 else if (Literal.isUTF8() && getLangOpts().Char8)
3286 Ty = Context.Char8Ty; // u8'x' -> char8_t when it exists.
3287 else if (Literal.isUTF16())
3288 Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11.
3289 else if (Literal.isUTF32())
3290 Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11.
3291 else if (!getLangOpts().CPlusPlus || Literal.isMultiChar())
3292 Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++.
3293 else
3294 Ty = Context.CharTy; // 'x' -> char in C++
3295
3296 CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii;
3297 if (Literal.isWide())
3298 Kind = CharacterLiteral::Wide;
3299 else if (Literal.isUTF16())
3300 Kind = CharacterLiteral::UTF16;
3301 else if (Literal.isUTF32())
3302 Kind = CharacterLiteral::UTF32;
3303 else if (Literal.isUTF8())
3304 Kind = CharacterLiteral::UTF8;
3305
3306 Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty,
3307 Tok.getLocation());
3308
3309 if (Literal.getUDSuffix().empty())
3310 return Lit;
3311
3312 // We're building a user-defined literal.
3313 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
3314 SourceLocation UDSuffixLoc =
3315 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
3316
3317 // Make sure we're allowed user-defined literals here.
3318 if (!UDLScope)
3319 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl));
3320
3321 // C++11 [lex.ext]p6: The literal L is treated as a call of the form
3322 // operator "" X (ch)
3323 return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc,
3324 Lit, Tok.getLocation());
3325}
3326
3327ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) {
3328 unsigned IntSize = Context.getTargetInfo().getIntWidth();
3329 return IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val),
3330 Context.IntTy, Loc);
3331}
3332
3333static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal,
3334 QualType Ty, SourceLocation Loc) {
3335 const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty);
3336
3337 using llvm::APFloat;
3338 APFloat Val(Format);
3339
3340 APFloat::opStatus result = Literal.GetFloatValue(Val);
3341
3342 // Overflow is always an error, but underflow is only an error if
3343 // we underflowed to zero (APFloat reports denormals as underflow).
3344 if ((result & APFloat::opOverflow) ||
3345 ((result & APFloat::opUnderflow) && Val.isZero())) {
3346 unsigned diagnostic;
3347 SmallString<20> buffer;
3348 if (result & APFloat::opOverflow) {
3349 diagnostic = diag::warn_float_overflow;
3350 APFloat::getLargest(Format).toString(buffer);
3351 } else {
3352 diagnostic = diag::warn_float_underflow;
3353 APFloat::getSmallest(Format).toString(buffer);
3354 }
3355
3356 S.Diag(Loc, diagnostic)
3357 << Ty
3358 << StringRef(buffer.data(), buffer.size());
3359 }
3360
3361 bool isExact = (result == APFloat::opOK);
3362 return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc);
3363}
3364
3365bool Sema::CheckLoopHintExpr(Expr *E, SourceLocation Loc) {
3366 assert(E && "Invalid expression");
3367
3368 if (E->isValueDependent())
3369 return false;
3370
3371 QualType QT = E->getType();
3372 if (!QT->isIntegerType() || QT->isBooleanType() || QT->isCharType()) {
3373 Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_type) << QT;
3374 return true;
3375 }
3376
3377 llvm::APSInt ValueAPS;
3378 ExprResult R = VerifyIntegerConstantExpression(E, &ValueAPS);
3379
3380 if (R.isInvalid())
3381 return true;
3382
3383 bool ValueIsPositive = ValueAPS.isStrictlyPositive();
3384 if (!ValueIsPositive || ValueAPS.getActiveBits() > 31) {
3385 Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_value)
3386 << ValueAPS.toString(10) << ValueIsPositive;
3387 return true;
3388 }
3389
3390 return false;
3391}
3392
3393ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) {
3394 // Fast path for a single digit (which is quite common). A single digit
3395 // cannot have a trigraph, escaped newline, radix prefix, or suffix.
3396 if (Tok.getLength() == 1) {
3397 const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok);
3398 return ActOnIntegerConstant(Tok.getLocation(), Val-'0');
3399 }
3400
3401 SmallString<128> SpellingBuffer;
3402 // NumericLiteralParser wants to overread by one character. Add padding to
3403 // the buffer in case the token is copied to the buffer. If getSpelling()
3404 // returns a StringRef to the memory buffer, it should have a null char at
3405 // the EOF, so it is also safe.
3406 SpellingBuffer.resize(Tok.getLength() + 1);
3407
3408 // Get the spelling of the token, which eliminates trigraphs, etc.
3409 bool Invalid = false;
3410 StringRef TokSpelling = PP.getSpelling(Tok, SpellingBuffer, &Invalid);
3411 if (Invalid)
3412 return ExprError();
3413
3414 NumericLiteralParser Literal(TokSpelling, Tok.getLocation(), PP);
3415 if (Literal.hadError)
3416 return ExprError();
3417
3418 if (Literal.hasUDSuffix()) {
3419 // We're building a user-defined literal.
3420 IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
3421 SourceLocation UDSuffixLoc =
3422 getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
3423
3424 // Make sure we're allowed user-defined literals here.
3425 if (!UDLScope)
3426 return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl));
3427
3428 QualType CookedTy;
3429 if (Literal.isFloatingLiteral()) {
3430 // C++11 [lex.ext]p4: If S contains a literal operator with parameter type
3431 // long double, the literal is treated as a call of the form
3432 // operator "" X (f L)
3433 CookedTy = Context.LongDoubleTy;
3434 } else {
3435 // C++11 [lex.ext]p3: If S contains a literal operator with parameter type
3436 // unsigned long long, the literal is treated as a call of the form
3437 // operator "" X (n ULL)
3438 CookedTy = Context.UnsignedLongLongTy;
3439 }
3440
3441 DeclarationName OpName =
3442 Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
3443 DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
3444 OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
3445
3446 SourceLocation TokLoc = Tok.getLocation();
3447
3448 // Perform literal operator lookup to determine if we're building a raw
3449 // literal or a cooked one.
3450 LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
3451 switch (LookupLiteralOperator(UDLScope, R, CookedTy,
3452 /*AllowRaw*/ true, /*AllowTemplate*/ true,
3453 /*AllowStringTemplate*/ false,
3454 /*DiagnoseMissing*/ !Literal.isImaginary)) {
3455 case LOLR_ErrorNoDiagnostic:
3456 // Lookup failure for imaginary constants isn't fatal, there's still the
3457 // GNU extension producing _Complex types.
3458 break;
3459 case LOLR_Error:
3460 return ExprError();
3461 case LOLR_Cooked: {
3462 Expr *Lit;
3463 if (Literal.isFloatingLiteral()) {
3464 Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation());
3465 } else {
3466 llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0);
3467 if (Literal.GetIntegerValue(ResultVal))
3468 Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
3469 << /* Unsigned */ 1;
3470 Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy,
3471 Tok.getLocation());
3472 }
3473 return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
3474 }
3475
3476 case LOLR_Raw: {
3477 // C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the
3478 // literal is treated as a call of the form
3479 // operator "" X ("n")
3480 unsigned Length = Literal.getUDSuffixOffset();
3481 QualType StrTy = Context.getConstantArrayType(
3482 Context.adjustStringLiteralBaseType(Context.CharTy.withConst()),
3483 llvm::APInt(32, Length + 1), ArrayType::Normal, 0);
3484 Expr *Lit = StringLiteral::Create(
3485 Context, StringRef(TokSpelling.data(), Length), StringLiteral::Ascii,
3486 /*Pascal*/false, StrTy, &TokLoc, 1);
3487 return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
3488 }
3489
3490 case LOLR_Template: {
3491 // C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator
3492 // template), L is treated as a call fo the form
3493 // operator "" X <'c1', 'c2', ... 'ck'>()
3494 // where n is the source character sequence c1 c2 ... ck.
3495 TemplateArgumentListInfo ExplicitArgs;
3496 unsigned CharBits = Context.getIntWidth(Context.CharTy);
3497 bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType();
3498 llvm::APSInt Value(CharBits, CharIsUnsigned);
3499 for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) {
3500 Value = TokSpelling[I];
3501 TemplateArgument Arg(Context, Value, Context.CharTy);
3502 TemplateArgumentLocInfo ArgInfo;
3503 ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
3504 }
3505 return BuildLiteralOperatorCall(R, OpNameInfo, None, TokLoc,
3506 &ExplicitArgs);
3507 }
3508 case LOLR_StringTemplate:
3509 llvm_unreachable("unexpected literal operator lookup result");
3510 }
3511 }
3512
3513 Expr *Res;
3514
3515 if (Literal.isFixedPointLiteral()) {
3516 QualType Ty;
3517
3518 if (Literal.isAccum) {
3519 if (Literal.isHalf) {
3520 Ty = Context.ShortAccumTy;
3521 } else if (Literal.isLong) {
3522 Ty = Context.LongAccumTy;
3523 } else {
3524 Ty = Context.AccumTy;
3525 }
3526 } else if (Literal.isFract) {
3527 if (Literal.isHalf) {
3528 Ty = Context.ShortFractTy;
3529 } else if (Literal.isLong) {
3530 Ty = Context.LongFractTy;
3531 } else {
3532 Ty = Context.FractTy;
3533 }
3534 }
3535
3536 if (Literal.isUnsigned) Ty = Context.getCorrespondingUnsignedType(Ty);
3537
3538 bool isSigned = !Literal.isUnsigned;
3539 unsigned scale = Context.getFixedPointScale(Ty);
3540 unsigned bit_width = Context.getTypeInfo(Ty).Width;
3541
3542 llvm::APInt Val(bit_width, 0, isSigned);
3543 bool Overflowed = Literal.GetFixedPointValue(Val, scale);
3544 bool ValIsZero = Val.isNullValue() && !Overflowed;
3545
3546 auto MaxVal = Context.getFixedPointMax(Ty).getValue();
3547 if (Literal.isFract && Val == MaxVal + 1 && !ValIsZero)
3548 // Clause 6.4.4 - The value of a constant shall be in the range of
3549 // representable values for its type, with exception for constants of a
3550 // fract type with a value of exactly 1; such a constant shall denote
3551 // the maximal value for the type.
3552 --Val;
3553 else if (Val.ugt(MaxVal) || Overflowed)
3554 Diag(Tok.getLocation(), diag::err_too_large_for_fixed_point);
3555
3556 Res = FixedPointLiteral::CreateFromRawInt(Context, Val, Ty,
3557 Tok.getLocation(), scale);
3558 } else if (Literal.isFloatingLiteral()) {
3559 QualType Ty;
3560 if (Literal.isHalf){
3561 if (getOpenCLOptions().isEnabled("cl_khr_fp16"))
3562 Ty = Context.HalfTy;
3563 else {
3564 Diag(Tok.getLocation(), diag::err_half_const_requires_fp16);
3565 return ExprError();
3566 }
3567 } else if (Literal.isFloat)
3568 Ty = Context.FloatTy;
3569 else if (Literal.isLong)
3570 Ty = Context.LongDoubleTy;
3571 else if (Literal.isFloat16)
3572 Ty = Context.Float16Ty;
3573 else if (Literal.isFloat128)
3574 Ty = Context.Float128Ty;
3575 else
3576 Ty = Context.DoubleTy;
3577
3578 Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation());
3579
3580 if (Ty == Context.DoubleTy) {
3581 if (getLangOpts().SinglePrecisionConstants) {
3582 const BuiltinType *BTy = Ty->getAs<BuiltinType>();
3583 if (BTy->getKind() != BuiltinType::Float) {
3584 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
3585 }
3586 } else if (getLangOpts().OpenCL &&
3587 !getOpenCLOptions().isEnabled("cl_khr_fp64")) {
3588 // Impose single-precision float type when cl_khr_fp64 is not enabled.
3589 Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64);
3590 Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
3591 }
3592 }
3593 } else if (!Literal.isIntegerLiteral()) {
3594 return ExprError();
3595 } else {
3596 QualType Ty;
3597
3598 // 'long long' is a C99 or C++11 feature.
3599 if (!getLangOpts().C99 && Literal.isLongLong) {
3600 if (getLangOpts().CPlusPlus)
3601 Diag(Tok.getLocation(),
3602 getLangOpts().CPlusPlus11 ?
3603 diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
3604 else
3605 Diag(Tok.getLocation(), diag::ext_c99_longlong);
3606 }
3607
3608 // Get the value in the widest-possible width.
3609 unsigned MaxWidth = Context.getTargetInfo().getIntMaxTWidth();
3610 llvm::APInt ResultVal(MaxWidth, 0);
3611
3612 if (Literal.GetIntegerValue(ResultVal)) {
3613 // If this value didn't fit into uintmax_t, error and force to ull.
3614 Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
3615 << /* Unsigned */ 1;
3616 Ty = Context.UnsignedLongLongTy;
3617 assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() &&
3618 "long long is not intmax_t?");
3619 } else {
3620 // If this value fits into a ULL, try to figure out what else it fits into
3621 // according to the rules of C99 6.4.4.1p5.
3622
3623 // Octal, Hexadecimal, and integers with a U suffix are allowed to
3624 // be an unsigned int.
3625 bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
3626
3627 // Check from smallest to largest, picking the smallest type we can.
3628 unsigned Width = 0;
3629
3630 // Microsoft specific integer suffixes are explicitly sized.
3631 if (Literal.MicrosoftInteger) {
3632 if (Literal.MicrosoftInteger == 8 && !Literal.isUnsigned) {
3633 Width = 8;
3634 Ty = Context.CharTy;
3635 } else {
3636 Width = Literal.MicrosoftInteger;
3637 Ty = Context.getIntTypeForBitwidth(Width,
3638 /*Signed=*/!Literal.isUnsigned);
3639 }
3640 }
3641
3642 if (Ty.isNull() && !Literal.isLong && !Literal.isLongLong) {
3643 // Are int/unsigned possibilities?
3644 unsigned IntSize = Context.getTargetInfo().getIntWidth();
3645
3646 // Does it fit in a unsigned int?
3647 if (ResultVal.isIntN(IntSize)) {
3648 // Does it fit in a signed int?
3649 if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
3650 Ty = Context.IntTy;
3651 else if (AllowUnsigned)
3652 Ty = Context.UnsignedIntTy;
3653 Width = IntSize;
3654 }
3655 }
3656
3657 // Are long/unsigned long possibilities?
3658 if (Ty.isNull() && !Literal.isLongLong) {
3659 unsigned LongSize = Context.getTargetInfo().getLongWidth();
3660
3661 // Does it fit in a unsigned long?
3662 if (ResultVal.isIntN(LongSize)) {
3663 // Does it fit in a signed long?
3664 if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
3665 Ty = Context.LongTy;
3666 else if (AllowUnsigned)
3667 Ty = Context.UnsignedLongTy;
3668 // Check according to the rules of C90 6.1.3.2p5. C++03 [lex.icon]p2
3669 // is compatible.
3670 else if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11) {
3671 const unsigned LongLongSize =
3672 Context.getTargetInfo().getLongLongWidth();
3673 Diag(Tok.getLocation(),
3674 getLangOpts().CPlusPlus
3675 ? Literal.isLong
3676 ? diag::warn_old_implicitly_unsigned_long_cxx
3677 : /*C++98 UB*/ diag::
3678 ext_old_implicitly_unsigned_long_cxx
3679 : diag::warn_old_implicitly_unsigned_long)
3680 << (LongLongSize > LongSize ? /*will have type 'long long'*/ 0
3681 : /*will be ill-formed*/ 1);
3682 Ty = Context.UnsignedLongTy;
3683 }
3684 Width = LongSize;
3685 }
3686 }
3687
3688 // Check long long if needed.
3689 if (Ty.isNull()) {
3690 unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth();
3691
3692 // Does it fit in a unsigned long long?
3693 if (ResultVal.isIntN(LongLongSize)) {
3694 // Does it fit in a signed long long?
3695 // To be compatible with MSVC, hex integer literals ending with the
3696 // LL or i64 suffix are always signed in Microsoft mode.
3697 if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 ||
3698 (getLangOpts().MSVCCompat && Literal.isLongLong)))
3699 Ty = Context.LongLongTy;
3700 else if (AllowUnsigned)
3701 Ty = Context.UnsignedLongLongTy;
3702 Width = LongLongSize;
3703 }
3704 }
3705
3706 // If we still couldn't decide a type, we probably have something that
3707 // does not fit in a signed long long, but has no U suffix.
3708 if (Ty.isNull()) {
3709 Diag(Tok.getLocation(), diag::ext_integer_literal_too_large_for_signed);
3710 Ty = Context.UnsignedLongLongTy;
3711 Width = Context.getTargetInfo().getLongLongWidth();
3712 }
3713
3714 if (ResultVal.getBitWidth() != Width)
3715 ResultVal = ResultVal.trunc(Width);
3716 }
3717 Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation());
3718 }
3719
3720 // If this is an imaginary literal, create the ImaginaryLiteral wrapper.
3721 if (Literal.isImaginary) {
3722 Res = new (Context) ImaginaryLiteral(Res,
3723 Context.getComplexType(Res->getType()));
3724
3725 Diag(Tok.getLocation(), diag::ext_imaginary_constant);
3726 }
3727 return Res;
3728}
3729
3730ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) {
3731 assert(E && "ActOnParenExpr() missing expr");
3732 return new (Context) ParenExpr(L, R, E);
3733}
3734
3735static bool CheckVecStepTraitOperandType(Sema &S, QualType T,
3736 SourceLocation Loc,
3737 SourceRange ArgRange) {
3738 // [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in
3739 // scalar or vector data type argument..."
3740 // Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic
3741 // type (C99 6.2.5p18) or void.
3742 if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) {
3743 S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type)
3744 << T << ArgRange;
3745 return true;
3746 }
3747
3748 assert((T->isVoidType() || !T->isIncompleteType()) &&
3749 "Scalar types should always be complete");
3750 return false;
3751}
3752
3753static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
3754 SourceLocation Loc,
3755 SourceRange ArgRange,
3756 UnaryExprOrTypeTrait TraitKind) {
3757 // Invalid types must be hard errors for SFINAE in C++.
3758 if (S.LangOpts.CPlusPlus)
3759 return true;
3760
3761 // C99 6.5.3.4p1:
3762 if (T->isFunctionType() &&
3763 (TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf ||
3764 TraitKind == UETT_PreferredAlignOf)) {
3765 // sizeof(function)/alignof(function) is allowed as an extension.
3766 S.Diag(Loc, diag::ext_sizeof_alignof_function_type)
3767 << TraitKind << ArgRange;
3768 return false;
3769 }
3770
3771 // Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
3772 // this is an error (OpenCL v1.1 s6.3.k)
3773 if (T->isVoidType()) {
3774 unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
3775 : diag::ext_sizeof_alignof_void_type;
3776 S.Diag(Loc, DiagID) << TraitKind << ArgRange;
3777 return false;
3778 }
3779
3780 return true;
3781}
3782
3783static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T,
3784 SourceLocation Loc,
3785 SourceRange ArgRange,
3786 UnaryExprOrTypeTrait TraitKind) {
3787 // Reject sizeof(interface) and sizeof(interface<proto>) if the
3788 // runtime doesn't allow it.
3789 if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) {
3790 S.Diag(Loc, diag::err_sizeof_nonfragile_interface)
3791 << T << (TraitKind == UETT_SizeOf)
3792 << ArgRange;
3793 return true;
3794 }
3795
3796 return false;
3797}
3798
3799/// Check whether E is a pointer from a decayed array type (the decayed
3800/// pointer type is equal to T) and emit a warning if it is.
3801static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T,
3802 Expr *E) {
3803 // Don't warn if the operation changed the type.
3804 if (T != E->getType())
3805 return;
3806
3807 // Now look for array decays.
3808 ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E);
3809 if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay)
3810 return;
3811
3812 S.Diag(Loc, diag::warn_sizeof_array_decay) << ICE->getSourceRange()
3813 << ICE->getType()
3814 << ICE->getSubExpr()->getType();
3815}
3816
3817/// Check the constraints on expression operands to unary type expression
3818/// and type traits.
3819///
3820/// Completes any types necessary and validates the constraints on the operand
3821/// expression. The logic mostly mirrors the type-based overload, but may modify
3822/// the expression as it completes the type for that expression through template
3823/// instantiation, etc.
3824bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
3825 UnaryExprOrTypeTrait ExprKind) {
3826 QualType ExprTy = E->getType();
3827 assert(!ExprTy->isReferenceType());
3828
3829 if (ExprKind == UETT_VecStep)
3830 return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(),
3831 E->getSourceRange());
3832
3833 // Whitelist some types as extensions
3834 if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(),
3835 E->getSourceRange(), ExprKind))
3836 return false;
3837
3838 // 'alignof' applied to an expression only requires the base element type of
3839 // the expression to be complete. 'sizeof' requires the expression's type to
3840 // be complete (and will attempt to complete it if it's an array of unknown
3841 // bound).
3842 if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
3843 if (RequireCompleteType(E->getExprLoc(),
3844 Context.getBaseElementType(E->getType()),
3845 diag::err_sizeof_alignof_incomplete_type, ExprKind,
3846 E->getSourceRange()))
3847 return true;
3848 } else {
3849 if (RequireCompleteExprType(E, diag::err_sizeof_alignof_incomplete_type,
3850 ExprKind, E->getSourceRange()))
3851 return true;
3852 }
3853
3854 // Completing the expression's type may have changed it.
3855 ExprTy = E->getType();
3856 assert(!ExprTy->isReferenceType());
3857
3858 if (ExprTy->isFunctionType()) {
3859 Diag(E->getExprLoc(), diag::err_sizeof_alignof_function_type)
3860 << ExprKind << E->getSourceRange();
3861 return true;
3862 }
3863
3864 // The operand for sizeof and alignof is in an unevaluated expression context,
3865 // so side effects could result in unintended consequences.
3866 if ((ExprKind == UETT_SizeOf || ExprKind == UETT_AlignOf ||
3867 ExprKind == UETT_PreferredAlignOf) &&
3868 !inTemplateInstantiation() && E->HasSideEffects(Context, false))
3869 Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context);
3870
3871 if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(),
3872 E->getSourceRange(), ExprKind))
3873 return true;
3874
3875 if (ExprKind == UETT_SizeOf) {
3876 if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) {
3877 if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) {
3878 QualType OType = PVD->getOriginalType();
3879 QualType Type = PVD->getType();
3880 if (Type->isPointerType() && OType->isArrayType()) {
3881 Diag(E->getExprLoc(), diag::warn_sizeof_array_param)
3882 << Type << OType;
3883 Diag(PVD->getLocation(), diag::note_declared_at);
3884 }
3885 }
3886 }
3887
3888 // Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array
3889 // decays into a pointer and returns an unintended result. This is most
3890 // likely a typo for "sizeof(array) op x".
3891 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E->IgnoreParens())) {
3892 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
3893 BO->getLHS());
3894 warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
3895 BO->getRHS());
3896 }
3897 }
3898
3899 return false;
3900}
3901
3902/// Check the constraints on operands to unary expression and type
3903/// traits.
3904///
3905/// This will complete any types necessary, and validate the various constraints
3906/// on those operands.
3907///
3908/// The UsualUnaryConversions() function is *not* called by this routine.
3909/// C99 6.3.2.1p[2-4] all state:
3910/// Except when it is the operand of the sizeof operator ...
3911///
3912/// C++ [expr.sizeof]p4
3913/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
3914/// standard conversions are not applied to the operand of sizeof.
3915///
3916/// This policy is followed for all of the unary trait expressions.
3917bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
3918 SourceLocation OpLoc,
3919 SourceRange ExprRange,
3920 UnaryExprOrTypeTrait ExprKind) {
3921 if (ExprType->isDependentType())
3922 return false;
3923
3924 // C++ [expr.sizeof]p2:
3925 // When applied to a reference or a reference type, the result
3926 // is the size of the referenced type.
3927 // C++11 [expr.alignof]p3:
3928 // When alignof is applied to a reference type, the result
3929 // shall be the alignment of the referenced type.
3930 if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>())
3931 ExprType = Ref->getPointeeType();
3932
3933 // C11 6.5.3.4/3, C++11 [expr.alignof]p3:
3934 // When alignof or _Alignof is applied to an array type, the result
3935 // is the alignment of the element type.
3936 if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf ||
3937 ExprKind == UETT_OpenMPRequiredSimdAlign)
3938 ExprType = Context.getBaseElementType(ExprType);
3939
3940 if (ExprKind == UETT_VecStep)
3941 return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange);
3942
3943 // Whitelist some types as extensions
3944 if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange,
3945 ExprKind))
3946 return false;
3947
3948 if (RequireCompleteType(OpLoc, ExprType,
3949 diag::err_sizeof_alignof_incomplete_type,
3950 ExprKind, ExprRange))
3951 return true;
3952
3953 if (ExprType->isFunctionType()) {
3954 Diag(OpLoc, diag::err_sizeof_alignof_function_type)
3955 << ExprKind << ExprRange;
3956 return true;
3957 }
3958
3959 if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange,
3960 ExprKind))
3961 return true;
3962
3963 return false;
3964}
3965
3966static bool CheckAlignOfExpr(Sema &S, Expr *E, UnaryExprOrTypeTrait ExprKind) {
3967 E = E->IgnoreParens();
3968
3969 // Cannot know anything else if the expression is dependent.
3970 if (E->isTypeDependent())
3971 return false;
3972
3973 if (E->getObjectKind() == OK_BitField) {
3974 S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield)
3975 << 1 << E->getSourceRange();
3976 return true;
3977 }
3978
3979 ValueDecl *D = nullptr;
3980 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
3981 D = DRE->getDecl();
3982 } else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3983 D = ME->getMemberDecl();
3984 }
3985
3986 // If it's a field, require the containing struct to have a
3987 // complete definition so that we can compute the layout.
3988 //
3989 // This can happen in C++11 onwards, either by naming the member
3990 // in a way that is not transformed into a member access expression
3991 // (in an unevaluated operand, for instance), or by naming the member
3992 // in a trailing-return-type.
3993 //
3994 // For the record, since __alignof__ on expressions is a GCC
3995 // extension, GCC seems to permit this but always gives the
3996 // nonsensical answer 0.
3997 //
3998 // We don't really need the layout here --- we could instead just
3999 // directly check for all the appropriate alignment-lowing
4000 // attributes --- but that would require duplicating a lot of
4001 // logic that just isn't worth duplicating for such a marginal
4002 // use-case.
4003 if (FieldDecl *FD = dyn_cast_or_null<FieldDecl>(D)) {
4004 // Fast path this check, since we at least know the record has a
4005 // definition if we can find a member of it.
4006 if (!FD->getParent()->isCompleteDefinition()) {
4007 S.Diag(E->getExprLoc(), diag::err_alignof_member_of_incomplete_type)
4008 << E->getSourceRange();
4009 return true;
4010 }
4011
4012 // Otherwise, if it's a field, and the field doesn't have
4013 // reference type, then it must have a complete type (or be a
4014 // flexible array member, which we explicitly want to
4015 // white-list anyway), which makes the following checks trivial.
4016 if (!FD->getType()->isReferenceType())
4017 return false;
4018 }
4019
4020 return S.CheckUnaryExprOrTypeTraitOperand(E, ExprKind);
4021}
4022
4023bool Sema::CheckVecStepExpr(Expr *E) {
4024 E = E->IgnoreParens();
4025
4026 // Cannot know anything else if the expression is dependent.
4027 if (E->isTypeDependent())
4028 return false;
4029
4030 return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep);
4031}
4032
4033static void captureVariablyModifiedType(ASTContext &Context, QualType T,
4034 CapturingScopeInfo *CSI) {
4035 assert(T->isVariablyModifiedType());
4036 assert(CSI != nullptr);
4037
4038 // We're going to walk down into the type and look for VLA expressions.
4039 do {
4040 const Type *Ty = T.getTypePtr();
4041 switch (Ty->getTypeClass()) {
4042#define TYPE(Class, Base)
4043#define ABSTRACT_TYPE(Class, Base)
4044#define NON_CANONICAL_TYPE(Class, Base)
4045#define DEPENDENT_TYPE(Class, Base) case Type::Class:
4046#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
4047#include "clang/AST/TypeNodes.def"
4048 T = QualType();
4049 break;
4050 // These types are never variably-modified.
4051 case Type::Builtin:
4052 case Type::Complex:
4053 case Type::Vector:
4054 case Type::ExtVector:
4055 case Type::Record:
4056 case Type::Enum:
4057 case Type::Elaborated:
4058 case Type::TemplateSpecialization:
4059 case Type::ObjCObject:
4060 case Type::ObjCInterface:
4061 case Type::ObjCObjectPointer:
4062 case Type::ObjCTypeParam:
4063 case Type::Pipe:
4064 llvm_unreachable("type class is never variably-modified!");
4065 case Type::Adjusted:
4066 T = cast<AdjustedType>(Ty)->getOriginalType();
4067 break;
4068 case Type::Decayed:
4069 T = cast<DecayedType>(Ty)->getPointeeType();
4070 break;
4071 case Type::Pointer:
4072 T = cast<PointerType>(Ty)->getPointeeType();
4073 break;
4074 case Type::BlockPointer:
4075 T = cast<BlockPointerType>(Ty)->getPointeeType();
4076 break;
4077 case Type::LValueReference:
4078 case Type::RValueReference:
4079 T = cast<ReferenceType>(Ty)->getPointeeType();
4080 break;
4081 case Type::MemberPointer:
4082 T = cast<MemberPointerType>(Ty)->getPointeeType();
4083 break;
4084 case Type::ConstantArray:
4085 case Type::IncompleteArray:
4086 // Losing element qualification here is fine.
4087 T = cast<ArrayType>(Ty)->getElementType();
4088 break;
4089 case Type::VariableArray: {
4090 // Losing element qualification here is fine.
4091 const VariableArrayType *VAT = cast<VariableArrayType>(Ty);
4092
4093 // Unknown size indication requires no size computation.
4094 // Otherwise, evaluate and record it.
4095 auto Size = VAT->getSizeExpr();
4096 if (Size && !CSI->isVLATypeCaptured(VAT) &&
4097 (isa<CapturedRegionScopeInfo>(CSI) || isa<LambdaScopeInfo>(CSI)))
4098 CSI->addVLATypeCapture(Size->getExprLoc(), VAT, Context.getSizeType());
4099
4100 T = VAT->getElementType();
4101 break;
4102 }
4103 case Type::FunctionProto:
4104 case Type::FunctionNoProto:
4105 T = cast<FunctionType>(Ty)->getReturnType();
4106 break;
4107 case Type::Paren:
4108 case Type::TypeOf:
4109 case Type::UnaryTransform:
4110 case Type::Attributed:
4111 case Type::SubstTemplateTypeParm:
4112 case Type::PackExpansion:
4113 case Type::MacroQualified:
4114 // Keep walking after single level desugaring.
4115 T = T.getSingleStepDesugaredType(Context);
4116 break;
4117 case Type::Typedef:
4118 T = cast<TypedefType>(Ty)->desugar();
4119 break;
4120 case Type::Decltype:
4121 T = cast<DecltypeType>(Ty)->desugar();
4122 break;
4123 case Type::Auto:
4124 case Type::DeducedTemplateSpecialization:
4125 T = cast<DeducedType>(Ty)->getDeducedType();
4126 break;
4127 case Type::TypeOfExpr:
4128 T = cast<TypeOfExprType>(Ty)->getUnderlyingExpr()->getType();
4129 break;
4130 case Type::Atomic:
4131 T = cast<AtomicType>(Ty)->getValueType();
4132 break;
4133 }
4134 } while (!T.isNull() && T->isVariablyModifiedType());
4135}
4136
4137/// Build a sizeof or alignof expression given a type operand.
4138ExprResult
4139Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
4140 SourceLocation OpLoc,
4141 UnaryExprOrTypeTrait ExprKind,
4142 SourceRange R) {
4143 if (!TInfo)
4144 return ExprError();
4145
4146 QualType T = TInfo->getType();
4147
4148 if (!T->isDependentType() &&
4149 CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind))
4150 return ExprError();
4151
4152 if (T->isVariablyModifiedType() && FunctionScopes.size() > 1) {
4153 if (auto *TT = T->getAs<TypedefType>()) {
4154 for (auto I = FunctionScopes.rbegin(),
4155 E = std::prev(FunctionScopes.rend());
4156 I != E; ++I) {
4157 auto *CSI = dyn_cast<CapturingScopeInfo>(*I);
4158 if (CSI == nullptr)
4159 break;
4160 DeclContext *DC = nullptr;
4161 if (auto *LSI = dyn_cast<LambdaScopeInfo>(CSI))
4162 DC = LSI->CallOperator;
4163 else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(CSI))
4164 DC = CRSI->TheCapturedDecl;
4165 else if (auto *BSI = dyn_cast<BlockScopeInfo>(CSI))
4166 DC = BSI->TheDecl;
4167 if (DC) {
4168 if (DC->containsDecl(TT->getDecl()))
4169 break;
4170 captureVariablyModifiedType(Context, T, CSI);
4171 }
4172 }
4173 }
4174 }
4175
4176 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4177 return new (Context) UnaryExprOrTypeTraitExpr(
4178 ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());
4179}
4180
4181/// Build a sizeof or alignof expression given an expression
4182/// operand.
4183ExprResult
4184Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
4185 UnaryExprOrTypeTrait ExprKind) {
4186 ExprResult PE = CheckPlaceholderExpr(E);
4187 if (PE.isInvalid())
4188 return ExprError();
4189
4190 E = PE.get();
4191
4192 // Verify that the operand is valid.
4193 bool isInvalid = false;
4194 if (E->isTypeDependent()) {
4195 // Delay type-checking for type-dependent expressions.
4196 } else if (ExprKind == UETT_AlignOf || ExprKind == UETT_PreferredAlignOf) {
4197 isInvalid = CheckAlignOfExpr(*this, E, ExprKind);
4198 } else if (ExprKind == UETT_VecStep) {
4199 isInvalid = CheckVecStepExpr(E);
4200 } else if (ExprKind == UETT_OpenMPRequiredSimdAlign) {
4201 Diag(E->getExprLoc(), diag::err_openmp_default_simd_align_expr);
4202 isInvalid = true;
4203 } else if (E->refersToBitField()) { // C99 6.5.3.4p1.
4204 Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield) << 0;
4205 isInvalid = true;
4206 } else {
4207 isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf);
4208 }
4209
4210 if (isInvalid)
4211 return ExprError();
4212
4213 if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) {
4214 PE = TransformToPotentiallyEvaluated(E);
4215 if (PE.isInvalid()) return ExprError();
4216 E = PE.get();
4217 }
4218
4219 // C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
4220 return new (Context) UnaryExprOrTypeTraitExpr(
4221 ExprKind, E, Context.getSizeType(), OpLoc, E->getSourceRange().getEnd());
4222}
4223
4224/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c
4225/// expr and the same for @c alignof and @c __alignof
4226/// Note that the ArgRange is invalid if isType is false.
4227ExprResult
4228Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
4229 UnaryExprOrTypeTrait ExprKind, bool IsType,
4230 void *TyOrEx, SourceRange ArgRange) {
4231 // If error parsing type, ignore.
4232 if (!TyOrEx) return ExprError();
4233
4234 if (IsType) {
4235 TypeSourceInfo *TInfo;
4236 (void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo);
4237 return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange);
4238 }
4239
4240 Expr *ArgEx = (Expr *)TyOrEx;
4241 ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind);
4242 return Result;
4243}
4244
4245static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc,
4246 bool IsReal) {
4247 if (V.get()->isTypeDependent())
4248 return S.Context.DependentTy;
4249
4250 // _Real and _Imag are only l-values for normal l-values.
4251 if (V.get()->getObjectKind() != OK_Ordinary) {
4252 V = S.DefaultLvalueConversion(V.get());
4253 if (V.isInvalid())
4254 return QualType();
4255 }
4256
4257 // These operators return the element type of a complex type.
4258 if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>())
4259 return CT->getElementType();
4260
4261 // Otherwise they pass through real integer and floating point types here.
4262 if (V.get()->getType()->isArithmeticType())
4263 return V.get()->getType();
4264
4265 // Test for placeholders.
4266 ExprResult PR = S.CheckPlaceholderExpr(V.get());
4267 if (PR.isInvalid()) return QualType();
4268 if (PR.get() != V.get()) {
4269 V = PR;
4270 return CheckRealImagOperand(S, V, Loc, IsReal);
4271 }
4272
4273 // Reject anything else.
4274 S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType()
4275 << (IsReal ? "__real" : "__imag");
4276 return QualType();
4277}
4278
4279
4280
4281ExprResult
4282Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
4283 tok::TokenKind Kind, Expr *Input) {
4284 UnaryOperatorKind Opc;
4285 switch (Kind) {
4286 default: llvm_unreachable("Unknown unary op!");
4287 case tok::plusplus: Opc = UO_PostInc; break;
4288 case tok::minusminus: Opc = UO_PostDec; break;
4289 }
4290
4291 // Since this might is a postfix expression, get rid of ParenListExprs.
4292 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input);
4293 if (Result.isInvalid()) return ExprError();
4294 Input = Result.get();
4295
4296 return BuildUnaryOp(S, OpLoc, Opc, Input);
4297}
4298
4299/// Diagnose if arithmetic on the given ObjC pointer is illegal.
4300///
4301/// \return true on error
4302static bool checkArithmeticOnObjCPointer(Sema &S,
4303 SourceLocation opLoc,
4304 Expr *op) {
4305 assert(op->getType()->isObjCObjectPointerType());
4306 if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic() &&
4307 !S.LangOpts.ObjCSubscriptingLegacyRuntime)
4308 return false;
4309
4310 S.Diag(opLoc, diag::err_arithmetic_nonfragile_interface)
4311 << op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType()
4312 << op->getSourceRange();
4313 return true;
4314}
4315
4316static bool isMSPropertySubscriptExpr(Sema &S, Expr *Base) {
4317 auto *BaseNoParens = Base->IgnoreParens();
4318 if (auto *MSProp = dyn_cast<MSPropertyRefExpr>(BaseNoParens))
4319 return MSProp->getPropertyDecl()->getType()->isArrayType();
4320 return isa<MSPropertySubscriptExpr>(BaseNoParens);
4321}
4322
4323ExprResult
4324Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base, SourceLocation lbLoc,
4325 Expr *idx, SourceLocation rbLoc) {
4326 if (base && !base->getType().isNull() &&
4327 base->getType()->isSpecificPlaceholderType(BuiltinType::OMPArraySection))
4328 return ActOnOMPArraySectionExpr(base, lbLoc, idx, SourceLocation(),
4329 /*Length=*/nullptr, rbLoc);
4330
4331 // Since this might be a postfix expression, get rid of ParenListExprs.
4332 if (isa<ParenListExpr>(base)) {
4333 ExprResult result = MaybeConvertParenListExprToParenExpr(S, base);
4334 if (result.isInvalid()) return ExprError();
4335 base = result.get();
4336 }
4337
4338 // Handle any non-overload placeholder types in the base and index
4339 // expressions. We can't handle overloads here because the other
4340 // operand might be an overloadable type, in which case the overload
4341 // resolution for the operator overload should get the first crack
4342 // at the overload.
4343 bool IsMSPropertySubscript = false;
4344 if (base->getType()->isNonOverloadPlaceholderType()) {
4345 IsMSPropertySubscript = isMSPropertySubscriptExpr(*this, base);
4346 if (!IsMSPropertySubscript) {
4347 ExprResult result = CheckPlaceholderExpr(base);
4348 if (result.isInvalid())
4349 return ExprError();
4350 base = result.get();
4351 }
4352 }
4353 if (idx->getType()->isNonOverloadPlaceholderType()) {
4354 ExprResult result = CheckPlaceholderExpr(idx);
4355 if (result.isInvalid()) return ExprError();
4356 idx = result.get();
4357 }
4358
4359 // Build an unanalyzed expression if either operand is type-dependent.
4360 if (getLangOpts().CPlusPlus &&
4361 (base->isTypeDependent() || idx->isTypeDependent())) {
4362 return new (Context) ArraySubscriptExpr(base, idx, Context.DependentTy,
4363 VK_LValue, OK_Ordinary, rbLoc);
4364 }
4365
4366 // MSDN, property (C++)
4367 // https://msdn.microsoft.com/en-us/library/yhfk0thd(v=vs.120).aspx
4368 // This attribute can also be used in the declaration of an empty array in a
4369 // class or structure definition. For example:
4370 // __declspec(property(get=GetX, put=PutX)) int x[];
4371 // The above statement indicates that x[] can be used with one or more array
4372 // indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b),
4373 // and p->x[a][b] = i will be turned into p->PutX(a, b, i);
4374 if (IsMSPropertySubscript) {
4375 // Build MS property subscript expression if base is MS property reference
4376 // or MS property subscript.
4377 return new (Context) MSPropertySubscriptExpr(
4378 base, idx, Context.PseudoObjectTy, VK_LValue, OK_Ordinary, rbLoc);
4379 }
4380
4381 // Use C++ overloaded-operator rules if either operand has record
4382 // type. The spec says to do this if either type is *overloadable*,
4383 // but enum types can't declare subscript operators or conversion
4384 // operators, so there's nothing interesting for overload resolution
4385 // to do if there aren't any record types involved.
4386 //
4387 // ObjC pointers have their own subscripting logic that is not tied
4388 // to overload resolution and so should not take this path.
4389 if (getLangOpts().CPlusPlus &&
4390 (base->getType()->isRecordType() ||
4391 (!base->getType()->isObjCObjectPointerType() &&
4392 idx->getType()->isRecordType()))) {
4393 return CreateOverloadedArraySubscriptExpr(lbLoc, rbLoc, base, idx);
4394 }
4395
4396 ExprResult Res = CreateBuiltinArraySubscriptExpr(base, lbLoc, idx, rbLoc);
4397
4398 if (!Res.isInvalid() && isa<ArraySubscriptExpr>(Res.get()))
4399 CheckSubscriptAccessOfNoDeref(cast<ArraySubscriptExpr>(Res.get()));
4400
4401 return Res;
4402}
4403
4404void Sema::CheckAddressOfNoDeref(const Expr *E) {
4405 ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
4406 const Expr *StrippedExpr = E->IgnoreParenImpCasts();
4407
4408 // For expressions like `&(*s).b`, the base is recorded and what should be
4409 // checked.
4410 const MemberExpr *Member = nullptr;
4411 while ((Member = dyn_cast<MemberExpr>(StrippedExpr)) && !Member->isArrow())
4412 StrippedExpr = Member->getBase()->IgnoreParenImpCasts();
4413
4414 LastRecord.PossibleDerefs.erase(StrippedExpr);
4415}
4416
4417void Sema::CheckSubscriptAccessOfNoDeref(const ArraySubscriptExpr *E) {
4418 QualType ResultTy = E->getType();
4419 ExpressionEvaluationContextRecord &LastRecord = ExprEvalContexts.back();
4420
4421 // Bail if the element is an array since it is not memory access.
4422 if (isa<ArrayType>(ResultTy))
4423 return;
4424
4425 if (ResultTy->hasAttr(attr::NoDeref)) {
4426 LastRecord.PossibleDerefs.insert(E);
4427 return;
4428 }
4429
4430 // Check if the base type is a pointer to a member access of a struct
4431 // marked with noderef.
4432 const Expr *Base = E->getBase();
4433 QualType BaseTy = Base->getType();
4434 if (!(isa<ArrayType>(BaseTy) || isa<PointerType>(BaseTy)))
4435 // Not a pointer access
4436 return;
4437
4438 const MemberExpr *Member = nullptr;
4439 while ((Member = dyn_cast<MemberExpr>(Base->IgnoreParenCasts())) &&
4440 Member->isArrow())
4441 Base = Member->getBase();
4442
4443 if (const auto *Ptr = dyn_cast<PointerType>(Base->getType())) {
4444 if (Ptr->getPointeeType()->hasAttr(attr::NoDeref))
4445 LastRecord.PossibleDerefs.insert(E);
4446 }
4447}
4448
4449ExprResult Sema::ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
4450 Expr *LowerBound,
4451 SourceLocation ColonLoc, Expr *Length,
4452 SourceLocation RBLoc) {
4453 if (Base->getType()->isPlaceholderType() &&
4454 !Base->getType()->isSpecificPlaceholderType(
4455 BuiltinType::OMPArraySection)) {
4456 ExprResult Result = CheckPlaceholderExpr(Base);
4457 if (Result.isInvalid())
4458 return ExprError();
4459 Base = Result.get();
4460 }
4461 if (LowerBound && LowerBound->getType()->isNonOverloadPlaceholderType()) {
4462 ExprResult Result = CheckPlaceholderExpr(LowerBound);
4463 if (Result.isInvalid())
4464 return ExprError();
4465 Result = DefaultLvalueConversion(Result.get());
4466 if (Result.isInvalid())
4467 return ExprError();
4468 LowerBound = Result.get();
4469 }
4470 if (Length && Length->getType()->isNonOverloadPlaceholderType()) {
4471 ExprResult Result = CheckPlaceholderExpr(Length);
4472 if (Result.isInvalid())
4473 return ExprError();
4474 Result = DefaultLvalueConversion(Result.get());
4475 if (Result.isInvalid())
4476 return ExprError();
4477 Length = Result.get();
4478 }
4479
4480 // Build an unanalyzed expression if either operand is type-dependent.
4481 if (Base->isTypeDependent() ||
4482 (LowerBound &&
4483 (LowerBound->isTypeDependent() || LowerBound->isValueDependent())) ||
4484 (Length && (Length->isTypeDependent() || Length->isValueDependent()))) {
4485 return new (Context)
4486 OMPArraySectionExpr(Base, LowerBound, Length, Context.DependentTy,
4487 VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
4488 }
4489
4490 // Perform default conversions.
4491 QualType OriginalTy = OMPArraySectionExpr::getBaseOriginalType(Base);
4492 QualType ResultTy;
4493 if (OriginalTy->isAnyPointerType()) {
4494 ResultTy = OriginalTy->getPointeeType();
4495 } else if (OriginalTy->isArrayType()) {
4496 ResultTy = OriginalTy->getAsArrayTypeUnsafe()->getElementType();
4497 } else {
4498 return ExprError(
4499 Diag(Base->getExprLoc(), diag::err_omp_typecheck_section_value)
4500 << Base->getSourceRange());
4501 }
4502 // C99 6.5.2.1p1
4503 if (LowerBound) {
4504 auto Res = PerformOpenMPImplicitIntegerConversion(LowerBound->getExprLoc(),
4505 LowerBound);
4506 if (Res.isInvalid())
4507 return ExprError(Diag(LowerBound->getExprLoc(),
4508 diag::err_omp_typecheck_section_not_integer)
4509 << 0 << LowerBound->getSourceRange());
4510 LowerBound = Res.get();
4511
4512 if (LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4513 LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4514 Diag(LowerBound->getExprLoc(), diag::warn_omp_section_is_char)
4515 << 0 << LowerBound->getSourceRange();
4516 }
4517 if (Length) {
4518 auto Res =
4519 PerformOpenMPImplicitIntegerConversion(Length->getExprLoc(), Length);
4520 if (Res.isInvalid())
4521 return ExprError(Diag(Length->getExprLoc(),
4522 diag::err_omp_typecheck_section_not_integer)
4523 << 1 << Length->getSourceRange());
4524 Length = Res.get();
4525
4526 if (Length->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4527 Length->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4528 Diag(Length->getExprLoc(), diag::warn_omp_section_is_char)
4529 << 1 << Length->getSourceRange();
4530 }
4531
4532 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
4533 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object
4534 // type. Note that functions are not objects, and that (in C99 parlance)
4535 // incomplete types are not object types.
4536 if (ResultTy->isFunctionType()) {
4537 Diag(Base->getExprLoc(), diag::err_omp_section_function_type)
4538 << ResultTy << Base->getSourceRange();
4539 return ExprError();
4540 }
4541
4542 if (RequireCompleteType(Base->getExprLoc(), ResultTy,
4543 diag::err_omp_section_incomplete_type, Base))
4544 return ExprError();
4545
4546 if (LowerBound && !OriginalTy->isAnyPointerType()) {
4547 Expr::EvalResult Result;
4548 if (LowerBound->EvaluateAsInt(Result, Context)) {
4549 // OpenMP 4.5, [2.4 Array Sections]
4550 // The array section must be a subset of the original array.
4551 llvm::APSInt LowerBoundValue = Result.Val.getInt();
4552 if (LowerBoundValue.isNegative()) {
4553 Diag(LowerBound->getExprLoc(), diag::err_omp_section_not_subset_of_array)
4554 << LowerBound->getSourceRange();
4555 return ExprError();
4556 }
4557 }
4558 }
4559
4560 if (Length) {
4561 Expr::EvalResult Result;
4562 if (Length->EvaluateAsInt(Result, Context)) {
4563 // OpenMP 4.5, [2.4 Array Sections]
4564 // The length must evaluate to non-negative integers.
4565 llvm::APSInt LengthValue = Result.Val.getInt();
4566 if (LengthValue.isNegative()) {
4567 Diag(Length->getExprLoc(), diag::err_omp_section_length_negative)
4568 << LengthValue.toString(/*Radix=*/10, /*Signed=*/true)
4569 << Length->getSourceRange();
4570 return ExprError();
4571 }
4572 }
4573 } else if (ColonLoc.isValid() &&
4574 (OriginalTy.isNull() || (!OriginalTy->isConstantArrayType() &&
4575 !OriginalTy->isVariableArrayType()))) {
4576 // OpenMP 4.5, [2.4 Array Sections]
4577 // When the size of the array dimension is not known, the length must be
4578 // specified explicitly.
4579 Diag(ColonLoc, diag::err_omp_section_length_undefined)
4580 << (!OriginalTy.isNull() && OriginalTy->isArrayType());
4581 return ExprError();
4582 }
4583
4584 if (!Base->getType()->isSpecificPlaceholderType(
4585 BuiltinType::OMPArraySection)) {
4586 ExprResult Result = DefaultFunctionArrayLvalueConversion(Base);
4587 if (Result.isInvalid())
4588 return ExprError();
4589 Base = Result.get();
4590 }
4591 return new (Context)
4592 OMPArraySectionExpr(Base, LowerBound, Length, Context.OMPArraySectionTy,
4593 VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
4594}
4595
4596ExprResult
4597Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
4598 Expr *Idx, SourceLocation RLoc) {
4599 Expr *LHSExp = Base;
4600 Expr *RHSExp = Idx;
4601
4602 ExprValueKind VK = VK_LValue;
4603 ExprObjectKind OK = OK_Ordinary;
4604
4605 // Per C++ core issue 1213, the result is an xvalue if either operand is
4606 // a non-lvalue array, and an lvalue otherwise.
4607 if (getLangOpts().CPlusPlus11) {
4608 for (auto *Op : {LHSExp, RHSExp}) {
4609 Op = Op->IgnoreImplicit();
4610 if (Op->getType()->isArrayType() && !Op->isLValue())
4611 VK = VK_XValue;
4612 }
4613 }
4614
4615 // Perform default conversions.
4616 if (!LHSExp->getType()->getAs<VectorType>()) {
4617 ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp);
4618 if (Result.isInvalid())
4619 return ExprError();
4620 LHSExp = Result.get();
4621 }
4622 ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp);
4623 if (Result.isInvalid())
4624 return ExprError();
4625 RHSExp = Result.get();
4626
4627 QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
4628
4629 // C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
4630 // to the expression *((e1)+(e2)). This means the array "Base" may actually be
4631 // in the subscript position. As a result, we need to derive the array base
4632 // and index from the expression types.
4633 Expr *BaseExpr, *IndexExpr;
4634 QualType ResultType;
4635 if (LHSTy->isDependentType() || RHSTy->isDependentType()) {
4636 BaseExpr = LHSExp;
4637 IndexExpr = RHSExp;
4638 ResultType = Context.DependentTy;
4639 } else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) {
4640 BaseExpr = LHSExp;
4641 IndexExpr = RHSExp;
4642 ResultType = PTy->getPointeeType();
4643 } else if (const ObjCObjectPointerType *PTy =
4644 LHSTy->getAs<ObjCObjectPointerType>()) {
4645 BaseExpr = LHSExp;
4646 IndexExpr = RHSExp;
4647
4648 // Use custom logic if this should be the pseudo-object subscript
4649 // expression.
4650 if (!LangOpts.isSubscriptPointerArithmetic())
4651 return BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, nullptr,
4652 nullptr);
4653
4654 ResultType = PTy->getPointeeType();
4655 } else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) {
4656 // Handle the uncommon case of "123[Ptr]".
4657 BaseExpr = RHSExp;
4658 IndexExpr = LHSExp;
4659 ResultType = PTy->getPointeeType();
4660 } else if (const ObjCObjectPointerType *PTy =
4661 RHSTy->getAs<ObjCObjectPointerType>()) {
4662 // Handle the uncommon case of "123[Ptr]".
4663 BaseExpr = RHSExp;
4664 IndexExpr = LHSExp;
4665 ResultType = PTy->getPointeeType();
4666 if (!LangOpts.isSubscriptPointerArithmetic()) {
4667 Diag(LLoc, diag::err_subscript_nonfragile_interface)
4668 << ResultType << BaseExpr->getSourceRange();
4669 return ExprError();
4670 }
4671 } else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) {
4672 BaseExpr = LHSExp; // vectors: V[123]
4673 IndexExpr = RHSExp;
4674 // We apply C++ DR1213 to vector subscripting too.
4675 if (getLangOpts().CPlusPlus11 && LHSExp->getValueKind() == VK_RValue) {
4676 ExprResult Materialized = TemporaryMaterializationConversion(LHSExp);
4677 if (Materialized.isInvalid())
4678 return ExprError();
4679 LHSExp = Materialized.get();
4680 }
4681 VK = LHSExp->getValueKind();
4682 if (VK != VK_RValue)
4683 OK = OK_VectorComponent;
4684
4685 ResultType = VTy->getElementType();
4686 QualType BaseType = BaseExpr->getType();
4687 Qualifiers BaseQuals = BaseType.getQualifiers();
4688 Qualifiers MemberQuals = ResultType.getQualifiers();
4689 Qualifiers Combined = BaseQuals + MemberQuals;
4690 if (Combined != MemberQuals)
4691 ResultType = Context.getQualifiedType(ResultType, Combined);
4692 } else if (LHSTy->isArrayType()) {
4693 // If we see an array that wasn't promoted by
4694 // DefaultFunctionArrayLvalueConversion, it must be an array that
4695 // wasn't promoted because of the C90 rule that doesn't
4696 // allow promoting non-lvalue arrays. Warn, then
4697 // force the promotion here.
4698 Diag(LHSExp->getBeginLoc(), diag::ext_subscript_non_lvalue)
4699 << LHSExp->getSourceRange();
4700 LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy),
4701 CK_ArrayToPointerDecay).get();
4702 LHSTy = LHSExp->getType();
4703
4704 BaseExpr = LHSExp;
4705 IndexExpr = RHSExp;
4706 ResultType = LHSTy->getAs<PointerType>()->getPointeeType();
4707 } else if (RHSTy->isArrayType()) {
4708 // Same as previous, except for 123[f().a] case
4709 Diag(RHSExp->getBeginLoc(), diag::ext_subscript_non_lvalue)
4710 << RHSExp->getSourceRange();
4711 RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy),
4712 CK_ArrayToPointerDecay).get();
4713 RHSTy = RHSExp->getType();
4714
4715 BaseExpr = RHSExp;
4716 IndexExpr = LHSExp;
4717 ResultType = RHSTy->getAs<PointerType>()->getPointeeType();
4718 } else {
4719 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value)
4720 << LHSExp->getSourceRange() << RHSExp->getSourceRange());
4721 }
4722 // C99 6.5.2.1p1
4723 if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
4724 return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer)
4725 << IndexExpr->getSourceRange());
4726
4727 if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
4728 IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
4729 && !IndexExpr->isTypeDependent())
4730 Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange();
4731
4732 // C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
4733 // C++ [expr.sub]p1: The type "T" shall be a completely-defined object
4734 // type. Note that Functions are not objects, and that (in C99 parlance)
4735 // incomplete types are not object types.
4736 if (ResultType->isFunctionType()) {
4737 Diag(BaseExpr->getBeginLoc(), diag::err_subscript_function_type)
4738 << ResultType << BaseExpr->getSourceRange();
4739 return ExprError();
4740 }
4741
4742 if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) {
4743 // GNU extension: subscripting on pointer to void
4744 Diag(LLoc, diag::ext_gnu_subscript_void_type)
4745 << BaseExpr->getSourceRange();
4746
4747 // C forbids expressions of unqualified void type from being l-values.
4748 // See IsCForbiddenLValueType.
4749 if (!ResultType.hasQualifiers()) VK = VK_RValue;
4750 } else if (!ResultType->isDependentType() &&
4751 RequireCompleteType(LLoc, ResultType,
4752 diag::err_subscript_incomplete_type, BaseExpr))
4753 return ExprError();
4754
4755 assert(VK == VK_RValue || LangOpts.CPlusPlus ||
4756 !ResultType.isCForbiddenLValueType());
4757
4758 return new (Context)
4759 ArraySubscriptExpr(LHSExp, RHSExp, ResultType, VK, OK, RLoc);
4760}
4761
4762bool Sema::CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
4763 ParmVarDecl *Param) {
4764 if (Param->hasUnparsedDefaultArg()) {
4765 Diag(CallLoc,
4766 diag::err_use_of_default_argument_to_function_declared_later) <<
4767 FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName();
4768 Diag(UnparsedDefaultArgLocs[Param],
4769 diag::note_default_argument_declared_here);
4770 return true;
4771 }
4772
4773 if (Param->hasUninstantiatedDefaultArg()) {
4774 Expr *UninstExpr = Param->getUninstantiatedDefaultArg();
4775
4776 EnterExpressionEvaluationContext EvalContext(
4777 *this, ExpressionEvaluationContext::PotentiallyEvaluated, Param);
4778
4779 // Instantiate the expression.
4780 //
4781 // FIXME: Pass in a correct Pattern argument, otherwise
4782 // getTemplateInstantiationArgs uses the lexical context of FD, e.g.
4783 //
4784 // template<typename T>
4785 // struct A {
4786 // static int FooImpl();
4787 //
4788 // template<typename Tp>
4789 // // bug: default argument A<T>::FooImpl() is evaluated with 2-level
4790 // // template argument list [[T], [Tp]], should be [[Tp]].
4791 // friend A<Tp> Foo(int a);
4792 // };
4793 //
4794 // template<typename T>
4795 // A<T> Foo(int a = A<T>::FooImpl());
4796 MultiLevelTemplateArgumentList MutiLevelArgList
4797 = getTemplateInstantiationArgs(FD, nullptr, /*RelativeToPrimary=*/true);
4798
4799 InstantiatingTemplate Inst(*this, CallLoc, Param,
4800 MutiLevelArgList.getInnermost());
4801 if (Inst.isInvalid())
4802 return true;
4803 if (Inst.isAlreadyInstantiating()) {
4804 Diag(Param->getBeginLoc(), diag::err_recursive_default_argument) << FD;
4805 Param->setInvalidDecl();
4806 return true;
4807 }
4808
4809 ExprResult Result;
4810 {
4811 // C++ [dcl.fct.default]p5:
4812 // The names in the [default argument] expression are bound, and
4813 // the semantic constraints are checked, at the point where the
4814 // default argument expression appears.
4815 ContextRAII SavedContext(*this, FD);
4816 LocalInstantiationScope Local(*this);
4817 Result = SubstInitializer(UninstExpr, MutiLevelArgList,
4818 /*DirectInit*/false);
4819 }
4820 if (Result.isInvalid())
4821 return true;
4822
4823 // Check the expression as an initializer for the parameter.
4824 InitializedEntity Entity
4825 = InitializedEntity::InitializeParameter(Context, Param);
4826 InitializationKind Kind = InitializationKind::CreateCopy(
4827 Param->getLocation(),
4828 /*FIXME:EqualLoc*/ UninstExpr->getBeginLoc());
4829 Expr *ResultE = Result.getAs<Expr>();
4830
4831 InitializationSequence InitSeq(*this, Entity, Kind, ResultE);
4832 Result = InitSeq.Perform(*this, Entity, Kind, ResultE);
4833 if (Result.isInvalid())
4834 return true;
4835
4836 Result =
4837 ActOnFinishFullExpr(Result.getAs<Expr>(), Param->getOuterLocStart(),
4838 /*DiscardedValue*/ false);
4839 if (Result.isInvalid())
4840 return true;
4841
4842 // Remember the instantiated default argument.
4843 Param->setDefaultArg(Result.getAs<Expr>());
4844 if (ASTMutationListener *L = getASTMutationListener()) {
4845 L->DefaultArgumentInstantiated(Param);
4846 }
4847 }
4848
4849 // If the default argument expression is not set yet, we are building it now.
4850 if (!Param->hasInit()) {
4851 Diag(Param->getBeginLoc(), diag::err_recursive_default_argument) << FD;
4852 Param->setInvalidDecl();
4853 return true;
4854 }
4855
4856 // If the default expression creates temporaries, we need to
4857 // push them to the current stack of expression temporaries so they'll
4858 // be properly destroyed.
4859 // FIXME: We should really be rebuilding the default argument with new
4860 // bound temporaries; see the comment in PR5810.
4861 // We don't need to do that with block decls, though, because
4862 // blocks in default argument expression can never capture anything.
4863 if (auto Init = dyn_cast<ExprWithCleanups>(Param->getInit())) {
4864 // Set the "needs cleanups" bit regardless of whether there are
4865 // any explicit objects.
4866 Cleanup.setExprNeedsCleanups(Init->cleanupsHaveSideEffects());
4867
4868 // Append all the objects to the cleanup list. Right now, this
4869 // should always be a no-op, because blocks in default argument
4870 // expressions should never be able to capture anything.
4871 assert(!Init->getNumObjects() &&
4872 "default argument expression has capturing blocks?");
4873 }
4874
4875 // We already type-checked the argument, so we know it works.
4876 // Just mark all of the declarations in this potentially-evaluated expression
4877 // as being "referenced".
4878 EnterExpressionEvaluationContext EvalContext(
4879 *this, ExpressionEvaluationContext::PotentiallyEvaluated, Param);
4880 MarkDeclarationsReferencedInExpr(Param->getDefaultArg(),
4881 /*SkipLocalVariables=*/true);
4882 return false;
4883}
4884
4885ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
4886 FunctionDecl *FD, ParmVarDecl *Param) {
4887 if (CheckCXXDefaultArgExpr(CallLoc, FD, Param))
4888 return ExprError();
4889 return CXXDefaultArgExpr::Create(Context, CallLoc, Param, CurContext);
4890}
4891
4892Sema::VariadicCallType
4893Sema::getVariadicCallType(FunctionDecl *FDecl, const FunctionProtoType *Proto,
4894 Expr *Fn) {
4895 if (Proto && Proto->isVariadic()) {
4896 if (dyn_cast_or_null<CXXConstructorDecl>(FDecl))
4897 return VariadicConstructor;
4898 else if (Fn && Fn->getType()->isBlockPointerType())
4899 return VariadicBlock;
4900 else if (FDecl) {
4901 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
4902 if (Method->isInstance())
4903 return VariadicMethod;
4904 } else if (Fn && Fn->getType() == Context.BoundMemberTy)
4905 return VariadicMethod;
4906 return VariadicFunction;
4907 }
4908 return VariadicDoesNotApply;
4909}
4910
4911namespace {
4912class FunctionCallCCC final : public FunctionCallFilterCCC {
4913public:
4914 FunctionCallCCC(Sema &SemaRef, const IdentifierInfo *FuncName,
4915 unsigned NumArgs, MemberExpr *ME)
4916 : FunctionCallFilterCCC(SemaRef, NumArgs, false, ME),
4917 FunctionName(FuncName) {}
4918
4919 bool ValidateCandidate(const TypoCorrection &candidate) override {
4920 if (!candidate.getCorrectionSpecifier() ||
4921 candidate.getCorrectionAsIdentifierInfo() != FunctionName) {
4922 return false;
4923 }
4924
4925 return FunctionCallFilterCCC::ValidateCandidate(candidate);
4926 }
4927
4928 std::unique_ptr<CorrectionCandidateCallback> clone() override {
4929 return llvm::make_unique<FunctionCallCCC>(*this);
4930 }
4931
4932private:
4933 const IdentifierInfo *const FunctionName;
4934};
4935}
4936
4937static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
4938 FunctionDecl *FDecl,
4939 ArrayRef<Expr *> Args) {
4940 MemberExpr *ME = dyn_cast<MemberExpr>(Fn);
4941 DeclarationName FuncName = FDecl->getDeclName();
4942 SourceLocation NameLoc = ME ? ME->getMemberLoc() : Fn->getBeginLoc();
4943
4944 FunctionCallCCC CCC(S, FuncName.getAsIdentifierInfo(), Args.size(), ME);
4945 if (TypoCorrection Corrected = S.CorrectTypo(
4946 DeclarationNameInfo(FuncName, NameLoc), Sema::LookupOrdinaryName,
4947 S.getScopeForContext(S.CurContext), nullptr, CCC,
4948 Sema::CTK_ErrorRecovery)) {
4949 if (NamedDecl *ND = Corrected.getFoundDecl()) {
4950 if (Corrected.isOverloaded()) {
4951 OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
4952 OverloadCandidateSet::iterator Best;
4953 for (NamedDecl *CD : Corrected) {
4954 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
4955 S.AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), Args,
4956 OCS);
4957 }
4958 switch (OCS.BestViableFunction(S, NameLoc, Best)) {
4959 case OR_Success:
4960 ND = Best->FoundDecl;
4961 Corrected.setCorrectionDecl(ND);
4962 break;
4963 default:
4964 break;
4965 }
4966 }
4967 ND = ND->getUnderlyingDecl();
4968 if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND))
4969 return Corrected;
4970 }
4971 }
4972 return TypoCorrection();
4973}
4974
4975/// ConvertArgumentsForCall - Converts the arguments specified in
4976/// Args/NumArgs to the parameter types of the function FDecl with
4977/// function prototype Proto. Call is the call expression itself, and
4978/// Fn is the function expression. For a C++ member function, this
4979/// routine does not attempt to convert the object argument. Returns
4980/// true if the call is ill-formed.
4981bool
4982Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
4983 FunctionDecl *FDecl,
4984 const FunctionProtoType *Proto,
4985 ArrayRef<Expr *> Args,
4986 SourceLocation RParenLoc,
4987 bool IsExecConfig) {
4988 // Bail out early if calling a builtin with custom typechecking.
4989 if (FDecl)
4990 if (unsigned ID = FDecl->getBuiltinID())
4991 if (Context.BuiltinInfo.hasCustomTypechecking(ID))
4992 return false;
4993
4994 // C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
4995 // assignment, to the types of the corresponding parameter, ...
4996 unsigned NumParams = Proto->getNumParams();
4997 bool Invalid = false;
4998 unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumParams;
4999 unsigned FnKind = Fn->getType()->isBlockPointerType()
5000 ? 1 /* block */
5001 : (IsExecConfig ? 3 /* kernel function (exec config) */
5002 : 0 /* function */);
5003
5004 // If too few arguments are available (and we don't have default
5005 // arguments for the remaining parameters), don't make the call.
5006 if (Args.size() < NumParams) {
5007 if (Args.size() < MinArgs) {
5008 TypoCorrection TC;
5009 if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
5010 unsigned diag_id =
5011 MinArgs == NumParams && !Proto->isVariadic()
5012 ? diag::err_typecheck_call_too_few_args_suggest
5013 : diag::err_typecheck_call_too_few_args_at_least_suggest;
5014 diagnoseTypo(TC, PDiag(diag_id) << FnKind << MinArgs
5015 << static_cast<unsigned>(Args.size())
5016 << TC.getCorrectionRange());
5017 } else if (MinArgs == 1 && FDecl && FDecl->getParamDecl(0)->getDeclName())
5018 Diag(RParenLoc,
5019 MinArgs == NumParams && !Proto->isVariadic()
5020 ? diag::err_typecheck_call_too_few_args_one
5021 : diag::err_typecheck_call_too_few_args_at_least_one)
5022 << FnKind << FDecl->getParamDecl(0) << Fn->getSourceRange();
5023 else
5024 Diag(RParenLoc, MinArgs == NumParams && !Proto->isVariadic()
5025 ? diag::err_typecheck_call_too_few_args
5026 : diag::err_typecheck_call_too_few_args_at_least)
5027 << FnKind << MinArgs << static_cast<unsigned>(Args.size())
5028 << Fn->getSourceRange();
5029
5030 // Emit the location of the prototype.
5031 if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
5032 Diag(FDecl->getBeginLoc(), diag::note_callee_decl) << FDecl;
5033
5034 return true;
5035 }
5036 // We reserve space for the default arguments when we create
5037 // the call expression, before calling ConvertArgumentsForCall.
5038 assert((Call->getNumArgs() == NumParams) &&
5039 "We should have reserved space for the default arguments before!");
5040 }
5041
5042 // If too many are passed and not variadic, error on the extras and drop
5043 // them.
5044 if (Args.size() > NumParams) {
5045 if (!Proto->isVariadic()) {
5046 TypoCorrection TC;
5047 if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
5048 unsigned diag_id =
5049 MinArgs == NumParams && !Proto->isVariadic()
5050 ? diag::err_typecheck_call_too_many_args_suggest
5051 : diag::err_typecheck_call_too_many_args_at_most_suggest;
5052 diagnoseTypo(TC, PDiag(diag_id) << FnKind << NumParams
5053 << static_cast<unsigned>(Args.size())
5054 << TC.getCorrectionRange());
5055 } else if (NumParams == 1 && FDecl &&
5056 FDecl->getParamDecl(0)->getDeclName())
5057 Diag(Args[NumParams]->getBeginLoc(),
5058 MinArgs == NumParams
5059 ? diag::err_typecheck_call_too_many_args_one
5060 : diag::err_typecheck_call_too_many_args_at_most_one)
5061 << FnKind << FDecl->getParamDecl(0)
5062 << static_cast<unsigned>(Args.size()) << Fn->getSourceRange()
5063 << SourceRange(Args[NumParams]->getBeginLoc(),
5064 Args.back()->getEndLoc());
5065 else
5066 Diag(Args[NumParams]->getBeginLoc(),
5067 MinArgs == NumParams
5068 ? diag::err_typecheck_call_too_many_args
5069 : diag::err_typecheck_call_too_many_args_at_most)
5070 << FnKind << NumParams << static_cast<unsigned>(Args.size())
5071 << Fn->getSourceRange()
5072 << SourceRange(Args[NumParams]->getBeginLoc(),
5073 Args.back()->getEndLoc());
5074
5075 // Emit the location of the prototype.
5076 if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
5077 Diag(FDecl->getBeginLoc(), diag::note_callee_decl) << FDecl;
5078
5079 // This deletes the extra arguments.
5080 Call->shrinkNumArgs(NumParams);
5081 return true;
5082 }
5083 }
5084 SmallVector<Expr *, 8> AllArgs;
5085 VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn);
5086
5087 Invalid = GatherArgumentsForCall(Call->getBeginLoc(), FDecl, Proto, 0, Args,
5088 AllArgs, CallType);
5089 if (Invalid)
5090 return true;
5091 unsigned TotalNumArgs = AllArgs.size();
5092 for (unsigned i = 0; i < TotalNumArgs; ++i)
5093 Call->setArg(i, AllArgs[i]);
5094
5095 return false;
5096}
5097
5098bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
5099 const FunctionProtoType *Proto,
5100 unsigned FirstParam, ArrayRef<Expr *> Args,
5101 SmallVectorImpl<Expr *> &AllArgs,
5102 VariadicCallType CallType, bool AllowExplicit,
5103 bool IsListInitialization) {
5104 unsigned NumParams = Proto->getNumParams();
5105 bool Invalid = false;
5106 size_t ArgIx = 0;
5107 // Continue to check argument types (even if we have too few/many args).
5108 for (unsigned i = FirstParam; i < NumParams; i++) {
5109 QualType ProtoArgType = Proto->getParamType(i);
5110
5111 Expr *Arg;
5112 ParmVarDecl *Param = FDecl ? FDecl->getParamDecl(i) : nullptr;
5113 if (ArgIx < Args.size()) {
5114 Arg = Args[ArgIx++];
5115
5116 if (RequireCompleteType(Arg->getBeginLoc(), ProtoArgType,
5117 diag::err_call_incomplete_argument, Arg))
5118 return true;
5119
5120 // Strip the unbridged-cast placeholder expression off, if applicable.
5121 bool CFAudited = false;
5122 if (Arg->getType() == Context.ARCUnbridgedCastTy &&
5123 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
5124 (!Param || !Param->hasAttr<CFConsumedAttr>()))
5125 Arg = stripARCUnbridgedCast(Arg);
5126 else if (getLangOpts().ObjCAutoRefCount &&
5127 FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
5128 (!Param || !Param->hasAttr<CFConsumedAttr>()))
5129 CFAudited = true;
5130
5131 if (Proto->getExtParameterInfo(i).isNoEscape())
5132 if (auto *BE = dyn_cast<BlockExpr>(Arg->IgnoreParenNoopCasts(Context)))
5133 BE->getBlockDecl()->setDoesNotEscape();
5134
5135 InitializedEntity Entity =
5136 Param ? InitializedEntity::InitializeParameter(Context, Param,
5137 ProtoArgType)
5138 : InitializedEntity::InitializeParameter(
5139 Context, ProtoArgType, Proto->isParamConsumed(i));
5140
5141 // Remember that parameter belongs to a CF audited API.
5142 if (CFAudited)
5143 Entity.setParameterCFAudited();
5144
5145 ExprResult ArgE = PerformCopyInitialization(
5146 Entity, SourceLocation(), Arg, IsListInitialization, AllowExplicit);
5147 if (ArgE.isInvalid())
5148 return true;
5149
5150 Arg = ArgE.getAs<Expr>();
5151 } else {
5152 assert(Param && "can't use default arguments without a known callee");
5153
5154 ExprResult ArgExpr = BuildCXXDefaultArgExpr(CallLoc, FDecl, Param);
5155 if (ArgExpr.isInvalid())
5156 return true;
5157
5158 Arg = ArgExpr.getAs<Expr>();
5159 }
5160
5161 // Check for array bounds violations for each argument to the call. This
5162 // check only triggers warnings when the argument isn't a more complex Expr
5163 // with its own checking, such as a BinaryOperator.
5164 CheckArrayAccess(Arg);
5165
5166 // Check for violations of C99 static array rules (C99 6.7.5.3p7).
5167 CheckStaticArrayArgument(CallLoc, Param, Arg);
5168
5169 AllArgs.push_back(Arg);
5170 }
5171
5172 // If this is a variadic call, handle args passed through "...".
5173 if (CallType != VariadicDoesNotApply) {
5174 // Assume that extern "C" functions with variadic arguments that
5175 // return __unknown_anytype aren't *really* variadic.
5176 if (Proto->getReturnType() == Context.UnknownAnyTy && FDecl &&
5177 FDecl->isExternC()) {
5178 for (Expr *A : Args.slice(ArgIx)) {
5179 QualType paramType; // ignored
5180 ExprResult arg = checkUnknownAnyArg(CallLoc, A, paramType);
5181 Invalid |= arg.isInvalid();
5182 AllArgs.push_back(arg.get());
5183 }
5184
5185 // Otherwise do argument promotion, (C99 6.5.2.2p7).
5186 } else {
5187 for (Expr *A : Args.slice(ArgIx)) {
5188 ExprResult Arg = DefaultVariadicArgumentPromotion(A, CallType, FDecl);
5189 Invalid |= Arg.isInvalid();
5190 AllArgs.push_back(Arg.get());
5191 }
5192 }
5193
5194 // Check for array bounds violations.
5195 for (Expr *A : Args.slice(ArgIx))
5196 CheckArrayAccess(A);
5197 }
5198 return Invalid;
5199}
5200
5201static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
5202 TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
5203 if (DecayedTypeLoc DTL = TL.getAs<DecayedTypeLoc>())
5204 TL = DTL.getOriginalLoc();
5205 if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>())
5206 S.Diag(PVD->getLocation(), diag::note_callee_static_array)
5207 << ATL.getLocalSourceRange();
5208}
5209
5210/// CheckStaticArrayArgument - If the given argument corresponds to a static
5211/// array parameter, check that it is non-null, and that if it is formed by
5212/// array-to-pointer decay, the underlying array is sufficiently large.
5213///
5214/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the
5215/// array type derivation, then for each call to the function, the value of the
5216/// corresponding actual argument shall provide access to the first element of
5217/// an array with at least as many elements as specified by the size expression.
5218void
5219Sema::CheckStaticArrayArgument(SourceLocation CallLoc,
5220 ParmVarDecl *Param,
5221 const Expr *ArgExpr) {
5222 // Static array parameters are not supported in C++.
5223 if (!Param || getLangOpts().CPlusPlus)
5224 return;
5225
5226 QualType OrigTy = Param->getOriginalType();
5227
5228 const ArrayType *AT = Context.getAsArrayType(OrigTy);
5229 if (!AT || AT->getSizeModifier() != ArrayType::Static)
5230 return;
5231
5232 if (ArgExpr->isNullPointerConstant(Context,
5233 Expr::NPC_NeverValueDependent)) {
5234 Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
5235 DiagnoseCalleeStaticArrayParam(*this, Param);
5236 return;
5237 }
5238
5239 const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT);
5240 if (!CAT)
5241 return;
5242
5243 const ConstantArrayType *ArgCAT =
5244 Context.getAsConstantArrayType(ArgExpr->IgnoreParenCasts()->getType());
5245 if (!ArgCAT)
5246 return;
5247
5248 if (getASTContext().hasSameUnqualifiedType(CAT->getElementType(),
5249 ArgCAT->getElementType())) {
5250 if (ArgCAT->getSize().ult(CAT->getSize())) {
5251 Diag(CallLoc, diag::warn_static_array_too_small)
5252 << ArgExpr->getSourceRange()
5253 << (unsigned)ArgCAT->getSize().getZExtValue()
5254 << (unsigned)CAT->getSize().getZExtValue() << 0;
5255 DiagnoseCalleeStaticArrayParam(*this, Param);
5256 }
5257 return;
5258 }
5259
5260 Optional<CharUnits> ArgSize =
5261 getASTContext().getTypeSizeInCharsIfKnown(ArgCAT);
5262 Optional<CharUnits> ParmSize = getASTContext().getTypeSizeInCharsIfKnown(CAT);
5263 if (ArgSize && ParmSize && *ArgSize < *ParmSize) {
5264 Diag(CallLoc, diag::warn_static_array_too_small)
5265 << ArgExpr->getSourceRange() << (unsigned)ArgSize->getQuantity()
5266 << (unsigned)ParmSize->getQuantity() << 1;
5267 DiagnoseCalleeStaticArrayParam(*this, Param);
5268 }
5269}
5270
5271/// Given a function expression of unknown-any type, try to rebuild it
5272/// to have a function type.
5273static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn);
5274
5275/// Is the given type a placeholder that we need to lower out
5276/// immediately during argument processing?
5277static bool isPlaceholderToRemoveAsArg(QualType type) {
5278 // Placeholders are never sugared.
5279 const BuiltinType *placeholder = dyn_cast<BuiltinType>(type);
5280 if (!placeholder) return false;
5281
5282 switch (placeholder->getKind()) {
5283 // Ignore all the non-placeholder types.
5284#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
5285 case BuiltinType::Id:
5286#include "clang/Basic/OpenCLImageTypes.def"
5287#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
5288 case BuiltinType::Id:
5289#include "clang/Basic/OpenCLExtensionTypes.def"
5290#define PLACEHOLDER_TYPE(ID, SINGLETON_ID)
5291#define BUILTIN_TYPE(ID, SINGLETON_ID) case BuiltinType::ID:
5292#include "clang/AST/BuiltinTypes.def"
5293 return false;
5294
5295 // We cannot lower out overload sets; they might validly be resolved
5296 // by the call machinery.
5297 case BuiltinType::Overload:
5298 return false;
5299
5300 // Unbridged casts in ARC can be handled in some call positions and
5301 // should be left in place.
5302 case BuiltinType::ARCUnbridgedCast:
5303 return false;
5304
5305 // Pseudo-objects should be converted as soon as possible.
5306 case BuiltinType::PseudoObject:
5307 return true;
5308
5309 // The debugger mode could theoretically but currently does not try
5310 // to resolve unknown-typed arguments based on known parameter types.
5311 case BuiltinType::UnknownAny:
5312 return true;
5313
5314 // These are always invalid as call arguments and should be reported.
5315 case BuiltinType::BoundMember:
5316 case BuiltinType::BuiltinFn:
5317 case BuiltinType::OMPArraySection:
5318 return true;
5319
5320 }
5321 llvm_unreachable("bad builtin type kind");
5322}
5323
5324/// Check an argument list for placeholders that we won't try to
5325/// handle later.
5326static bool checkArgsForPlaceholders(Sema &S, MultiExprArg args) {
5327 // Apply this processing to all the arguments at once instead of
5328 // dying at the first failure.
5329 bool hasInvalid = false;
5330 for (size_t i = 0, e = args.size(); i != e; i++) {
5331 if (isPlaceholderToRemoveAsArg(args[i]->getType())) {
5332 ExprResult result = S.CheckPlaceholderExpr(args[i]);
5333 if (result.isInvalid()) hasInvalid = true;
5334 else args[i] = result.get();
5335 } else if (hasInvalid) {
5336 (void)S.CorrectDelayedTyposInExpr(args[i]);
5337 }
5338 }
5339 return hasInvalid;
5340}
5341
5342/// If a builtin function has a pointer argument with no explicit address
5343/// space, then it should be able to accept a pointer to any address
5344/// space as input. In order to do this, we need to replace the
5345/// standard builtin declaration with one that uses the same address space
5346/// as the call.
5347///
5348/// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
5349/// it does not contain any pointer arguments without
5350/// an address space qualifer. Otherwise the rewritten
5351/// FunctionDecl is returned.
5352/// TODO: Handle pointer return types.
5353static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
5354 const FunctionDecl *FDecl,
5355 MultiExprArg ArgExprs) {
5356
5357 QualType DeclType = FDecl->getType();
5358 const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(DeclType);
5359
5360 if (!Context.BuiltinInfo.hasPtrArgsOrResult(FDecl->getBuiltinID()) ||
5361 !FT || FT->isVariadic() || ArgExprs.size() != FT->getNumParams())
5362 return nullptr;
5363
5364 bool NeedsNewDecl = false;
5365 unsigned i = 0;
5366 SmallVector<QualType, 8> OverloadParams;
5367
5368 for (QualType ParamType : FT->param_types()) {
5369
5370 // Convert array arguments to pointer to simplify type lookup.
5371 ExprResult ArgRes =
5372 Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]);
5373 if (ArgRes.isInvalid())
5374 return nullptr;
5375 Expr *Arg = ArgRes.get();
5376 QualType ArgType = Arg->getType();
5377 if (!ParamType->isPointerType() ||
5378 ParamType.getQualifiers().hasAddressSpace() ||
5379 !ArgType->isPointerType() ||
5380 !ArgType->getPointeeType().getQualifiers().hasAddressSpace()) {
5381 OverloadParams.push_back(ParamType);
5382 continue;
5383 }
5384
5385 QualType PointeeType = ParamType->getPointeeType();
5386 if (PointeeType.getQualifiers().hasAddressSpace())
5387 continue;
5388
5389 NeedsNewDecl = true;
5390 LangAS AS = ArgType->getPointeeType().getAddressSpace();
5391
5392 PointeeType = Context.getAddrSpaceQualType(PointeeType, AS);
5393 OverloadParams.push_back(Context.getPointerType(PointeeType));
5394 }
5395
5396 if (!NeedsNewDecl)
5397 return nullptr;
5398
5399 FunctionProtoType::ExtProtoInfo EPI;
5400 QualType OverloadTy = Context.getFunctionType(FT->getReturnType(),
5401 OverloadParams, EPI);
5402 DeclContext *Parent = Context.getTranslationUnitDecl();
5403 FunctionDecl *OverloadDecl = FunctionDecl::Create(Context, Parent,
5404 FDecl->getLocation(),
5405 FDecl->getLocation(),
5406 FDecl->getIdentifier(),
5407 OverloadTy,
5408 /*TInfo=*/nullptr,
5409 SC_Extern, false,
5410 /*hasPrototype=*/true);
5411 SmallVector<ParmVarDecl*, 16> Params;
5412 FT = cast<FunctionProtoType>(OverloadTy);
5413 for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
5414 QualType ParamType = FT->getParamType(i);
5415 ParmVarDecl *Parm =
5416 ParmVarDecl::Create(Context, OverloadDecl, SourceLocation(),
5417 SourceLocation(), nullptr, ParamType,
5418 /*TInfo=*/nullptr, SC_None, nullptr);
5419 Parm->setScopeInfo(0, i);
5420 Params.push_back(Parm);
5421 }
5422 OverloadDecl->setParams(Params);
5423 return OverloadDecl;
5424}
5425
5426static void checkDirectCallValidity(Sema &S, const Expr *Fn,
5427 FunctionDecl *Callee,
5428 MultiExprArg ArgExprs) {
5429
5430 // For purecap CHERI, output a warning if the callee doesn't have a prototype
5431 // and we are passing arguments. This would normally lead to using the
5432 // variadic calling convention. In the case of MIPS CHERI, this could lead to
5433 // runtime stack corruption if the callee function is not actually variadic.
5434 if (S.Context.getTargetInfo().SupportsCapabilities()) {
5435 bool NoProto = !Callee->getBuiltinID() && Callee->getType()->isFunctionNoProtoType();
5436 if (NoProto && ArgExprs.size() > 0) {
5437 S.Diag(Fn->getBeginLoc(), diag::warn_mips_cheri_call_no_func_proto)
5438 << Callee->getName() << Fn->getSourceRange();
5439 S.Diag(Callee->getLocation(), diag::note_mips_cheri_func_decl_add_types);
5440 S.Diag(Fn->getBeginLoc(), diag::note_mips_cheri_func_noproto_explanation);
5441 return;
5442 }
5443 }
5444
5445 // `Callee` (when called with ArgExprs) may be ill-formed. enable_if (and
5446 // similar attributes) really don't like it when functions are called with an
5447 // invalid number of args.
5448 if (S.TooManyArguments(Callee->getNumParams(), ArgExprs.size(),
5449 /*PartialOverloading=*/false) &&
5450 !Callee->isVariadic())
5451 return;
5452 if (Callee->getMinRequiredArguments() > ArgExprs.size())
5453 return;
5454
5455 if (const EnableIfAttr *Attr = S.CheckEnableIf(Callee, ArgExprs, true)) {
5456 S.Diag(Fn->getBeginLoc(),
5457 isa<CXXMethodDecl>(Callee)
5458 ? diag::err_ovl_no_viable_member_function_in_call
5459 : diag::err_ovl_no_viable_function_in_call)
5460 << Callee << Callee->getSourceRange();
5461 S.Diag(Callee->getLocation(),
5462 diag::note_ovl_candidate_disabled_by_function_cond_attr)
5463 << Attr->getCond()->getSourceRange() << Attr->getMessage();
5464 return;
5465 }
5466}
5467
5468static bool enclosingClassIsRelatedToClassInWhichMembersWereFound(
5469 const UnresolvedMemberExpr *const UME, Sema &S) {
5470
5471 const auto GetFunctionLevelDCIfCXXClass =
5472 [](Sema &S) -> const CXXRecordDecl * {
5473 const DeclContext *const DC = S.getFunctionLevelDeclContext();
5474 if (!DC || !DC->getParent())
5475 return nullptr;
5476
5477 // If the call to some member function was made from within a member
5478 // function body 'M' return return 'M's parent.
5479 if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
5480 return MD->getParent()->getCanonicalDecl();
5481 // else the call was made from within a default member initializer of a
5482 // class, so return the class.
5483 if (const auto *RD = dyn_cast<CXXRecordDecl>(DC))
5484 return RD->getCanonicalDecl();
5485 return nullptr;
5486 };
5487 // If our DeclContext is neither a member function nor a class (in the
5488 // case of a lambda in a default member initializer), we can't have an
5489 // enclosing 'this'.
5490
5491 const CXXRecordDecl *const CurParentClass = GetFunctionLevelDCIfCXXClass(S);
5492 if (!CurParentClass)
5493 return false;
5494
5495 // The naming class for implicit member functions call is the class in which
5496 // name lookup starts.
5497 const CXXRecordDecl *const NamingClass =
5498 UME->getNamingClass()->getCanonicalDecl();
5499 assert(NamingClass && "Must have naming class even for implicit access");
5500
5501 // If the unresolved member functions were found in a 'naming class' that is
5502 // related (either the same or derived from) to the class that contains the
5503 // member function that itself contained the implicit member access.
5504
5505 return CurParentClass == NamingClass ||
5506 CurParentClass->isDerivedFrom(NamingClass);
5507}
5508
5509static void
5510tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
5511 Sema &S, const UnresolvedMemberExpr *const UME, SourceLocation CallLoc) {
5512
5513 if (!UME)
5514 return;
5515
5516 LambdaScopeInfo *const CurLSI = S.getCurLambda();
5517 // Only try and implicitly capture 'this' within a C++ Lambda if it hasn't
5518 // already been captured, or if this is an implicit member function call (if
5519 // it isn't, an attempt to capture 'this' should already have been made).
5520 if (!CurLSI || CurLSI->ImpCaptureStyle == CurLSI->ImpCap_None ||
5521 !UME->isImplicitAccess() || CurLSI->isCXXThisCaptured())
5522 return;
5523
5524 // Check if the naming class in which the unresolved members were found is
5525 // related (same as or is a base of) to the enclosing class.
5526
5527 if (!enclosingClassIsRelatedToClassInWhichMembersWereFound(UME, S))
5528 return;
5529
5530
5531 DeclContext *EnclosingFunctionCtx = S.CurContext->getParent()->getParent();
5532 // If the enclosing function is not dependent, then this lambda is
5533 // capture ready, so if we can capture this, do so.
5534 if (!EnclosingFunctionCtx->isDependentContext()) {
5535 // If the current lambda and all enclosing lambdas can capture 'this' -
5536 // then go ahead and capture 'this' (since our unresolved overload set
5537 // contains at least one non-static member function).
5538 if (!S.CheckCXXThisCapture(CallLoc, /*Explcit*/ false, /*Diagnose*/ false))
5539 S.CheckCXXThisCapture(CallLoc);
5540 } else if (S.CurContext->isDependentContext()) {
5541 // ... since this is an implicit member reference, that might potentially
5542 // involve a 'this' capture, mark 'this' for potential capture in
5543 // enclosing lambdas.
5544 if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
5545 CurLSI->addPotentialThisCapture(CallLoc);
5546 }
5547}
5548
5549ExprResult Sema::ActOnCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
5550 MultiExprArg ArgExprs, SourceLocation RParenLoc,
5551 Expr *ExecConfig) {
5552 ExprResult Call =
5553 BuildCallExpr(Scope, Fn, LParenLoc, ArgExprs, RParenLoc, ExecConfig);
5554 if (Call.isInvalid())
5555 return Call;
5556
5557 // Diagnose uses of the C++20 "ADL-only template-id call" feature in earlier
5558 // language modes.
5559 if (auto *ULE = dyn_cast<UnresolvedLookupExpr>(Fn)) {
5560 if (ULE->hasExplicitTemplateArgs() &&
5561 ULE->decls_begin() == ULE->decls_end()) {
5562 Diag(Fn->getExprLoc(), getLangOpts().CPlusPlus2a
5563 ? diag::warn_cxx17_compat_adl_only_template_id
5564 : diag::ext_adl_only_template_id)
5565 << ULE->getName();
5566 }
5567 }
5568
5569 return Call;
5570}
5571
5572/// BuildCallExpr - Handle a call to Fn with the specified array of arguments.
5573/// This provides the location of the left/right parens and a list of comma
5574/// locations.
5575ExprResult Sema::BuildCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
5576 MultiExprArg ArgExprs, SourceLocation RParenLoc,
5577 Expr *ExecConfig, bool IsExecConfig) {
5578 // Since this might be a postfix expression, get rid of ParenListExprs.
5579 ExprResult Result = MaybeConvertParenListExprToParenExpr(Scope, Fn);
5580 if (Result.isInvalid()) return ExprError();
5581 Fn = Result.get();
5582
5583 if (checkArgsForPlaceholders(*this, ArgExprs))
5584 return ExprError();
5585
5586 if (getLangOpts().CPlusPlus) {
5587 // If this is a pseudo-destructor expression, build the call immediately.
5588 if (isa<CXXPseudoDestructorExpr>(Fn)) {
5589 if (!ArgExprs.empty()) {
5590 // Pseudo-destructor calls should not have any arguments.
5591 Diag(Fn->getBeginLoc(), diag::err_pseudo_dtor_call_with_args)
5592 << FixItHint::CreateRemoval(
5593 SourceRange(ArgExprs.front()->getBeginLoc(),
5594 ArgExprs.back()->getEndLoc()));
5595 }
5596
5597 return CallExpr::Create(Context, Fn, /*Args=*/{}, Context.VoidTy,
5598 VK_RValue, RParenLoc);
5599 }
5600 if (Fn->getType() == Context.PseudoObjectTy) {
5601 ExprResult result = CheckPlaceholderExpr(Fn);
5602 if (result.isInvalid()) return ExprError();
5603 Fn = result.get();
5604 }
5605
5606 // Determine whether this is a dependent call inside a C++ template,
5607 // in which case we won't do any semantic analysis now.
5608 if (Fn->isTypeDependent() || Expr::hasAnyTypeDependentArguments(ArgExprs)) {
5609 if (ExecConfig) {
5610 return CUDAKernelCallExpr::Create(
5611 Context, Fn, cast<CallExpr>(ExecConfig), ArgExprs,
5612 Context.DependentTy, VK_RValue, RParenLoc);
5613 } else {
5614
5615 tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
5616 *this, dyn_cast<UnresolvedMemberExpr>(Fn->IgnoreParens()),
5617 Fn->getBeginLoc());
5618
5619 return CallExpr::Create(Context, Fn, ArgExprs, Context.DependentTy,
5620 VK_RValue, RParenLoc);
5621 }
5622 }
5623
5624 // Determine whether this is a call to an object (C++ [over.call.object]).
5625 if (Fn->getType()->isRecordType())
5626 return BuildCallToObjectOfClassType(Scope, Fn, LParenLoc, ArgExprs,
5627 RParenLoc);
5628
5629 if (Fn->getType() == Context.UnknownAnyTy) {
5630 ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
5631 if (result.isInvalid()) return ExprError();
5632 Fn = result.get();
5633 }
5634
5635 if (Fn->getType() == Context.BoundMemberTy) {
5636 return BuildCallToMemberFunction(Scope, Fn, LParenLoc, ArgExprs,
5637 RParenLoc);
5638 }
5639 }
5640
5641 // Check for overloaded calls. This can happen even in C due to extensions.
5642 if (Fn->getType() == Context.OverloadTy) {
5643 OverloadExpr::FindResult find = OverloadExpr::find(Fn);
5644
5645 // We aren't supposed to apply this logic if there's an '&' involved.
5646 if (!find.HasFormOfMemberPointer) {
5647 if (Expr::hasAnyTypeDependentArguments(ArgExprs))
5648 return CallExpr::Create(Context, Fn, ArgExprs, Context.DependentTy,
5649 VK_RValue, RParenLoc);
5650 OverloadExpr *ovl = find.Expression;
5651 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(ovl))
5652 return BuildOverloadedCallExpr(
5653 Scope, Fn, ULE, LParenLoc, ArgExprs, RParenLoc, ExecConfig,
5654 /*AllowTypoCorrection=*/true, find.IsAddressOfOperand);
5655 return BuildCallToMemberFunction(Scope, Fn, LParenLoc, ArgExprs,
5656 RParenLoc);
5657 }
5658 }
5659
5660 // If we're directly calling a function, get the appropriate declaration.
5661 if (Fn->getType() == Context.UnknownAnyTy) {
5662 ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
5663 if (result.isInvalid()) return ExprError();
5664 Fn = result.get();
5665 }
5666
5667 Expr *NakedFn = Fn->IgnoreParens();
5668
5669 bool CallingNDeclIndirectly = false;
5670 NamedDecl *NDecl = nullptr;
5671 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) {
5672 if (UnOp->getOpcode() == UO_AddrOf) {
5673 CallingNDeclIndirectly = true;
5674 NakedFn = UnOp->getSubExpr()->IgnoreParens();
5675 }
5676 }
5677
5678 if (auto *DRE = dyn_cast<DeclRefExpr>(NakedFn)) {
5679 NDecl = DRE->getDecl();
5680
5681 FunctionDecl *FDecl = dyn_cast<FunctionDecl>(NDecl);
5682 if (FDecl && FDecl->getBuiltinID()) {
5683 // Rewrite the function decl for this builtin by replacing parameters
5684 // with no explicit address space with the address space of the arguments
5685 // in ArgExprs.
5686 if ((FDecl =
5687 rewriteBuiltinFunctionDecl(this, Context, FDecl, ArgExprs))) {
5688 NDecl = FDecl;
5689 Fn = DeclRefExpr::Create(
5690 Context, FDecl->getQualifierLoc(), SourceLocation(), FDecl, false,
5691 SourceLocation(), FDecl->getType(), Fn->getValueKind(), FDecl,
5692 nullptr, DRE->isNonOdrUse());
5693 }
5694 }
5695 } else if (isa<MemberExpr>(NakedFn))
5696 NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl();
5697
5698 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(NDecl)) {
5699 if (CallingNDeclIndirectly && !checkAddressOfFunctionIsAvailable(
5700 FD, /*Complain=*/true, Fn->getBeginLoc()))
5701 return ExprError();
5702
5703 if (getLangOpts().OpenCL && checkOpenCLDisabledDecl(*FD, *Fn))
5704 return ExprError();
5705
5706 checkDirectCallValidity(*this, Fn, FD, ArgExprs);
5707 }
5708
5709 return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs, RParenLoc,
5710 ExecConfig, IsExecConfig);
5711}
5712
5713/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments.
5714///
5715/// __builtin_astype( value, dst type )
5716///
5717ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
5718 SourceLocation BuiltinLoc,
5719 SourceLocation RParenLoc) {
5720 ExprValueKind VK = VK_RValue;
5721 ExprObjectKind OK = OK_Ordinary;
5722 QualType DstTy = GetTypeFromParser(ParsedDestTy);
5723 QualType SrcTy = E->getType();
5724 if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy))
5725 return ExprError(Diag(BuiltinLoc,
5726 diag::err_invalid_astype_of_different_size)
5727 << DstTy
5728 << SrcTy
5729 << E->getSourceRange());
5730 return new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, RParenLoc);
5731}
5732
5733/// ActOnConvertVectorExpr - create a new convert-vector expression from the
5734/// provided arguments.
5735///
5736/// __builtin_convertvector( value, dst type )
5737///
5738ExprResult Sema::ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
5739 SourceLocation BuiltinLoc,
5740 SourceLocation RParenLoc) {
5741 TypeSourceInfo *TInfo;
5742 GetTypeFromParser(ParsedDestTy, &TInfo);
5743 return SemaConvertVectorExpr(E, TInfo, BuiltinLoc, RParenLoc);
5744}
5745
5746/// BuildResolvedCallExpr - Build a call to a resolved expression,
5747/// i.e. an expression not of \p OverloadTy. The expression should
5748/// unary-convert to an expression of function-pointer or
5749/// block-pointer type.
5750///
5751/// \param NDecl the declaration being called, if available
5752ExprResult Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
5753 SourceLocation LParenLoc,
5754 ArrayRef<Expr *> Args,
5755 SourceLocation RParenLoc, Expr *Config,
5756 bool IsExecConfig, ADLCallKind UsesADL) {
5757 FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl);
5758 unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0);
5759
5760 if (!BuiltinID)
5761 if (NamedDecl *currentDecl = getCurFunctionOrMethodDecl())
5762 if (currentDecl->hasAttr<SensitiveAttr>() &&
5763 (!FDecl || !FDecl->hasAttr<SensitiveAttr>()))
5764 Diag(RParenLoc, diag::warn_calling_non_sensitive_from_sensitive)
5765 << FDecl << currentDecl;
5766
5767
5768 // Functions with 'interrupt' attribute cannot be called directly.
5769 if (FDecl && FDecl->hasAttr<AnyX86InterruptAttr>()) {
5770 Diag(Fn->getExprLoc(), diag::err_anyx86_interrupt_called);
5771 return ExprError();
5772 }
5773
5774 // Interrupt handlers don't save off the VFP regs automatically on ARM,
5775 // so there's some risk when calling out to non-interrupt handler functions
5776 // that the callee might not preserve them. This is easy to diagnose here,
5777 // but can be very challenging to debug.
5778 if (auto *Caller = getCurFunctionDecl())
5779 if (Caller->hasAttr<ARMInterruptAttr>()) {
5780 bool VFP = Context.getTargetInfo().hasFeature("vfp");
5781 if (VFP && (!FDecl || !FDecl->hasAttr<ARMInterruptAttr>()))
5782 Diag(Fn->getExprLoc(), diag::warn_arm_interrupt_calling_convention);
5783 }
5784
5785 // Promote the function operand.
5786 // We special-case function promotion here because we only allow promoting
5787 // builtin functions to function pointers in the callee of a call.
5788 ExprResult Result;
5789 QualType ResultTy;
5790 if (BuiltinID &&
5791 Fn->getType()->isSpecificBuiltinType(BuiltinType::BuiltinFn)) {
5792 // Extract the return type from the (builtin) function pointer type.
5793 // FIXME Several builtins still have setType in
5794 // Sema::CheckBuiltinFunctionCall. One should review their definitions in
5795 // Builtins.def to ensure they are correct before removing setType calls.
5796 QualType FnPtrTy = Context.getPointerType(FDecl->getType());
5797 Result = ImpCastExprToType(Fn, FnPtrTy, CK_BuiltinFnToFnPtr).get();
5798 ResultTy = FDecl->getCallResultType();
5799 } else {
5800 Result = CallExprUnaryConversions(Fn);
5801 ResultTy = Context.BoolTy;
5802 }
5803 if (Result.isInvalid())
5804 return ExprError();
5805 Fn = Result.get();
5806
5807 // Check for a valid function type, but only if it is not a builtin which
5808 // requires custom type checking. These will be handled by
5809 // CheckBuiltinFunctionCall below just after creation of the call expression.
5810 const FunctionType *FuncT = nullptr;
5811 if (!BuiltinID || !Context.BuiltinInfo.hasCustomTypechecking(BuiltinID)) {
5812 retry:
5813 if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) {
5814 // C99 6.5.2.2p1 - "The expression that denotes the called function shall
5815 // have type pointer to function".
5816 FuncT = PT->getPointeeType()->getAs<FunctionType>();
5817 if (!FuncT)
5818 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
5819 << Fn->getType() << Fn->getSourceRange());
5820 } else if (const BlockPointerType *BPT =
5821 Fn->getType()->getAs<BlockPointerType>()) {
5822 FuncT = BPT->getPointeeType()->castAs<FunctionType>();
5823 } else {
5824 // Handle calls to expressions of unknown-any type.
5825 if (Fn->getType() == Context.UnknownAnyTy) {
5826 ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn);
5827 if (rewrite.isInvalid()) return ExprError();
5828 Fn = rewrite.get();
5829 goto retry;
5830 }
5831
5832 return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
5833 << Fn->getType() << Fn->getSourceRange());
5834 }
5835 }
5836
5837 // Get the number of parameters in the function prototype, if any.
5838 // We will allocate space for max(Args.size(), NumParams) arguments
5839 // in the call expression.
5840 const auto *Proto = dyn_cast_or_null<FunctionProtoType>(FuncT);
5841 unsigned NumParams = Proto ? Proto->getNumParams() : 0;
5842
5843 CallExpr *TheCall;
5844 if (Config) {
5845 assert(UsesADL == ADLCallKind::NotADL &&
5846 "CUDAKernelCallExpr should not use ADL");
5847 TheCall =
5848 CUDAKernelCallExpr::Create(Context, Fn, cast<CallExpr>(Config), Args,
5849 ResultTy, VK_RValue, RParenLoc, NumParams);
5850 } else {
5851 TheCall = CallExpr::Create(Context, Fn, Args, ResultTy, VK_RValue,
5852 RParenLoc, NumParams, UsesADL);
5853 }
5854
5855 if (!getLangOpts().CPlusPlus) {
5856 // Forget about the nulled arguments since typo correction
5857 // do not handle them well.
5858 TheCall->shrinkNumArgs(Args.size());
5859 // C cannot always handle TypoExpr nodes in builtin calls and direct
5860 // function calls as their argument checking don't necessarily handle
5861 // dependent types properly, so make sure any TypoExprs have been
5862 // dealt with.
5863 ExprResult Result = CorrectDelayedTyposInExpr(TheCall);
5864 if (!Result.isUsable()) return ExprError();
5865 CallExpr *TheOldCall = TheCall;
5866 TheCall = dyn_cast<CallExpr>(Result.get());
5867 bool CorrectedTypos = TheCall != TheOldCall;
5868 if (!TheCall) return Result;
5869 Args = llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs());
5870
5871 // A new call expression node was created if some typos were corrected.
5872 // However it may not have been constructed with enough storage. In this
5873 // case, rebuild the node with enough storage. The waste of space is
5874 // immaterial since this only happens when some typos were corrected.
5875 if (CorrectedTypos && Args.size() < NumParams) {
5876 if (Config)
5877 TheCall = CUDAKernelCallExpr::Create(
5878 Context, Fn, cast<CallExpr>(Config), Args, ResultTy, VK_RValue,
5879 RParenLoc, NumParams);
5880 else
5881 TheCall = CallExpr::Create(Context, Fn, Args, ResultTy, VK_RValue,
5882 RParenLoc, NumParams, UsesADL);
5883 }
5884 // We can now handle the nulled arguments for the default arguments.
5885 TheCall->setNumArgsUnsafe(std::max<unsigned>(Args.size(), NumParams));
5886 }
5887
5888 // Bail out early if calling a builtin with custom type checking.
5889 if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID))
5890 return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
5891
5892 if (getLangOpts().CUDA) {
5893 if (Config) {
5894 // CUDA: Kernel calls must be to global functions
5895 if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>())
5896 return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function)
5897 << FDecl << Fn->getSourceRange());
5898
5899 // CUDA: Kernel function must have 'void' return type
5900 if (!FuncT->getReturnType()->isVoidType())
5901 return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return)
5902 << Fn->getType() << Fn->getSourceRange());
5903 } else {
5904 // CUDA: Calls to global functions must be configured
5905 if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>())
5906 return ExprError(Diag(LParenLoc, diag::err_global_call_not_config)
5907 << FDecl << Fn->getSourceRange());
5908 }
5909 }
5910
5911 // Check for a valid return type
5912 if (CheckCallReturnType(FuncT->getReturnType(), Fn->getBeginLoc(), TheCall,
5913 FDecl))
5914 return ExprError();
5915
5916 // We know the result type of the call, set it.
5917 TheCall->setType(FuncT->getCallResultType(Context));
5918 TheCall->setValueKind(Expr::getValueKindForType(FuncT->getReturnType()));
5919
5920 if (Proto) {
5921 if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, RParenLoc,
5922 IsExecConfig))
5923 return ExprError();
5924 } else {
5925 assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!");
5926
5927 if (FDecl) {
5928 // Check if we have too few/too many template arguments, based
5929 // on our knowledge of the function definition.
5930 const FunctionDecl *Def = nullptr;
5931 if (FDecl->hasBody(Def) && Args.size() != Def->param_size()) {
5932 Proto = Def->getType()->getAs<FunctionProtoType>();
5933 if (!Proto || !(Proto->isVariadic() && Args.size() >= Def->param_size()))
5934 Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments)
5935 << (Args.size() > Def->param_size()) << FDecl << Fn->getSourceRange();
5936 }
5937
5938 // If the function we're calling isn't a function prototype, but we have
5939 // a function prototype from a prior declaratiom, use that prototype.
5940 if (!FDecl->hasPrototype())
5941 Proto = FDecl->getType()->getAs<FunctionProtoType>();
5942 }
5943
5944 // Promote the arguments (C99 6.5.2.2p6).
5945 for (unsigned i = 0, e = Args.size(); i != e; i++) {
5946 Expr *Arg = Args[i];
5947
5948 if (Proto && i < Proto->getNumParams()) {
5949 InitializedEntity Entity = InitializedEntity::InitializeParameter(
5950 Context, Proto->getParamType(i), Proto->isParamConsumed(i));
5951 ExprResult ArgE =
5952 PerformCopyInitialization(Entity, SourceLocation(), Arg);
5953 if (ArgE.isInvalid())
5954 return true;
5955
5956 Arg = ArgE.getAs<Expr>();
5957
5958 } else {
5959 ExprResult ArgE = DefaultArgumentPromotion(Arg);
5960
5961 if (ArgE.isInvalid())
5962 return true;
5963
5964 Arg = ArgE.getAs<Expr>();
5965 }
5966
5967 if (RequireCompleteType(Arg->getBeginLoc(), Arg->getType(),
5968 diag::err_call_incomplete_argument, Arg))
5969 return ExprError();
5970
5971 TheCall->setArg(i, Arg);
5972 }
5973 }
5974
5975 if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
5976 if (!Method->isStatic())
5977 return ExprError(Diag(LParenLoc, diag::err_member_call_without_object)
5978 << Fn->getSourceRange());
5979
5980 // Check for sentinels
5981 if (NDecl)
5982 DiagnoseSentinelCalls(NDecl, LParenLoc, Args);
5983
5984 // Do special checking on direct calls to functions.
5985 if (FDecl) {
5986 if (CheckFunctionCall(FDecl, TheCall, Proto))
5987 return ExprError();
5988
5989 checkFortifiedBuiltinMemoryFunction(FDecl, TheCall);
5990
5991 if (BuiltinID)
5992 return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
5993 } else if (NDecl) {
5994 if (CheckPointerCall(NDecl, TheCall, Proto))
5995 return ExprError();
5996 } else {
5997 if (CheckOtherCall(TheCall, Proto))
5998 return ExprError();
5999 }
6000
6001 return MaybeBindToTemporary(TheCall);
6002}
6003
6004ExprResult
6005Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
6006 SourceLocation RParenLoc, Expr *InitExpr) {
6007 assert(Ty && "ActOnCompoundLiteral(): missing type");
6008 assert(InitExpr && "ActOnCompoundLiteral(): missing expression");
6009
6010 TypeSourceInfo *TInfo;
6011 QualType literalType = GetTypeFromParser(Ty, &TInfo);
6012 if (!TInfo)
6013 TInfo = Context.getTrivialTypeSourceInfo(literalType);
6014
6015 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr);
6016}
6017
6018ExprResult
6019Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo,
6020 SourceLocation RParenLoc, Expr *LiteralExpr) {
6021 QualType literalType = TInfo->getType();
6022
6023 if (literalType->isArrayType()) {
6024 if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType),
6025 diag::err_illegal_decl_array_incomplete_type,
6026 SourceRange(LParenLoc,
6027 LiteralExpr->getSourceRange().getEnd())))
6028 return ExprError();
6029 if (literalType->isVariableArrayType())
6030 return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init)
6031 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd()));
6032 } else if (!literalType->isDependentType() &&
6033 RequireCompleteType(LParenLoc, literalType,
6034 diag::err_typecheck_decl_incomplete_type,
6035 SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
6036 return ExprError();
6037
6038 InitializedEntity Entity
6039 = InitializedEntity::InitializeCompoundLiteralInit(TInfo);
6040 InitializationKind Kind
6041 = InitializationKind::CreateCStyleCast(LParenLoc,
6042 SourceRange(LParenLoc, RParenLoc),
6043 /*InitList=*/true);
6044 InitializationSequence InitSeq(*this, Entity, Kind, LiteralExpr);
6045 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, LiteralExpr,
6046 &literalType);
6047 if (Result.isInvalid())
6048 return ExprError();
6049 LiteralExpr = Result.get();
6050
6051 bool isFileScope = !CurContext->isFunctionOrMethod();
6052
6053 // In C, compound literals are l-values for some reason.
6054 // For GCC compatibility, in C++, file-scope array compound literals with
6055 // constant initializers are also l-values, and compound literals are
6056 // otherwise prvalues.
6057 //
6058 // (GCC also treats C++ list-initialized file-scope array prvalues with
6059 // constant initializers as l-values, but that's non-conforming, so we don't
6060 // follow it there.)
6061 //
6062 // FIXME: It would be better to handle the lvalue cases as materializing and
6063 // lifetime-extending a temporary object, but our materialized temporaries
6064 // representation only supports lifetime extension from a variable, not "out
6065 // of thin air".
6066 // FIXME: For C++, we might want to instead lifetime-extend only if a pointer
6067 // is bound to the result of applying array-to-pointer decay to the compound
6068 // literal.
6069 // FIXME: GCC supports compound literals of reference type, which should
6070 // obviously have a value kind derived from the kind of reference involved.
6071 ExprValueKind VK =
6072 (getLangOpts().CPlusPlus && !(isFileScope && literalType->isArrayType()))
6073 ? VK_RValue
6074 : VK_LValue;
6075
6076 if (isFileScope)
6077 if (auto ILE = dyn_cast<InitListExpr>(LiteralExpr))
6078 for (unsigned i = 0, j = ILE->getNumInits(); i != j; i++) {
6079 Expr *Init = ILE->getInit(i);
6080 ILE->setInit(i, ConstantExpr::Create(Context, Init));
6081 }
6082
6083 Expr *E = new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType,
6084 VK, LiteralExpr, isFileScope);
6085 if (isFileScope) {
6086 if (!LiteralExpr->isTypeDependent() &&
6087 !LiteralExpr->isValueDependent() &&
6088 !literalType->isDependentType()) // C99 6.5.2.5p3
6089 if (CheckForConstantInitializer(LiteralExpr, literalType))
6090 return ExprError();
6091 } else if (literalType.getAddressSpace() != LangAS::opencl_private &&
6092 literalType.getAddressSpace() != LangAS::Default) {
6093 // Embedded-C extensions to C99 6.5.2.5:
6094 // "If the compound literal occurs inside the body of a function, the
6095 // type name shall not be qualified by an address-space qualifier."
6096 Diag(LParenLoc, diag::err_compound_literal_with_address_space)
6097 << SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd());
6098 return ExprError();
6099 }
6100
6101 return MaybeBindToTemporary(E);
6102}
6103
6104ExprResult
6105Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
6106 SourceLocation RBraceLoc) {
6107 // Immediately handle non-overload placeholders. Overloads can be
6108 // resolved contextually, but everything else here can't.
6109 for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
6110 if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) {
6111 ExprResult result = CheckPlaceholderExpr(InitArgList[I]);
6112
6113 // Ignore failures; dropping the entire initializer list because
6114 // of one failure would be terrible for indexing/etc.
6115 if (result.isInvalid()) continue;
6116
6117 InitArgList[I] = result.get();
6118 }
6119 }
6120
6121 // Semantic analysis for initializers is done by ActOnDeclarator() and
6122 // CheckInitializer() - it requires knowledge of the object being initialized.
6123
6124 InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitArgList,
6125 RBraceLoc);
6126 E->setType(Context.VoidTy); // FIXME: just a place holder for now.
6127 return E;
6128}
6129
6130/// Do an explicit extend of the given block pointer if we're in ARC.
6131void Sema::maybeExtendBlockObject(ExprResult &E) {
6132 assert(E.get()->getType()->isBlockPointerType());
6133 assert(E.get()->isRValue());
6134
6135 // Only do this in an r-value context.
6136 if (!getLangOpts().ObjCAutoRefCount) return;
6137
6138 E = ImplicitCastExpr::Create(Context, E.get()->getType(),
6139 CK_ARCExtendBlockObject, E.get(),
6140 /*base path*/ nullptr, VK_RValue);
6141 Cleanup.setExprNeedsCleanups(true);
6142}
6143
6144/// Prepare a conversion of the given expression to an ObjC object
6145/// pointer type.
6146CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) {
6147 QualType type = E.get()->getType();
6148 if (type->isObjCObjectPointerType()) {
6149 return CK_BitCast;
6150 } else if (type->isBlockPointerType()) {
6151 maybeExtendBlockObject(E);
6152 return CK_BlockPointerToObjCPointerCast;
6153 } else {
6154 assert(type->isPointerType());
6155 return CK_CPointerToObjCPointerCast;
6156 }
6157}
6158
6159/// Prepares for a scalar cast, performing all the necessary stages
6160/// except the final cast and returning the kind required.
6161CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) {
6162 // Both Src and Dest are scalar types, i.e. arithmetic or pointer.
6163 // Also, callers should have filtered out the invalid cases with
6164 // pointers. Everything else should be possible.
6165
6166 QualType SrcTy = Src.get()->getType();
6167 if (Context.hasSameUnqualifiedType(SrcTy, DestTy))
6168 return CK_NoOp;
6169
6170 switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) {
6171 case Type::STK_MemberPointer:
6172 llvm_unreachable("member pointer type in C");
6173
6174 case Type::STK_CPointer:
6175 case Type::STK_BlockPointer:
6176 case Type::STK_ObjCObjectPointer:
6177 switch (DestTy->getScalarTypeKind()) {
6178 case Type::STK_CPointer: {
6179 LangAS SrcAS = SrcTy->getPointeeType().getAddressSpace();
6180 LangAS DestAS = DestTy->getPointeeType().getAddressSpace();
6181 if (SrcAS != DestAS)
6182 return CK_AddressSpaceConversion;
6183 else if (!SrcTy->isCHERICapabilityType(Context) && DestTy->isCHERICapabilityType(Context))
6184 return CK_PointerToCHERICapability;
6185 else if (SrcTy->isCHERICapabilityType(Context) && !DestTy->isCHERICapabilityType(Context))
6186 return CK_CHERICapabilityToPointer;
6187 else if (Context.hasCvrSimilarType(SrcTy, DestTy))
6188 return CK_NoOp;
6189 return CK_BitCast;
6190 }
6191 case Type::STK_BlockPointer:
6192 return (SrcKind == Type::STK_BlockPointer
6193 ? CK_BitCast : CK_AnyPointerToBlockPointerCast);
6194 case Type::STK_ObjCObjectPointer:
6195 if (SrcKind == Type::STK_ObjCObjectPointer)
6196 return CK_BitCast;
6197 if (SrcKind == Type::STK_CPointer)
6198 return CK_CPointerToObjCPointerCast;
6199 maybeExtendBlockObject(Src);
6200 return CK_BlockPointerToObjCPointerCast;
6201 case Type::STK_Bool:
6202 return CK_PointerToBoolean;
6203 case Type::STK_Integral:
6204 return CK_PointerToIntegral;
6205 case Type::STK_Floating:
6206 case Type::STK_FloatingComplex:
6207 case Type::STK_IntegralComplex:
6208 case Type::STK_MemberPointer:
6209 case Type::STK_FixedPoint:
6210 llvm_unreachable("illegal cast from pointer");
6211 }
6212 llvm_unreachable("Should have returned before this");
6213
6214 case Type::STK_FixedPoint:
6215 switch (DestTy->getScalarTypeKind()) {
6216 case Type::STK_FixedPoint:
6217 return CK_FixedPointCast;
6218 case Type::STK_Bool:
6219 return CK_FixedPointToBoolean;
6220 case Type::STK_Integral:
6221 return CK_FixedPointToIntegral;
6222 case Type::STK_Floating:
6223 case Type::STK_IntegralComplex:
6224 case Type::STK_FloatingComplex:
6225 Diag(Src.get()->getExprLoc(),
6226 diag::err_unimplemented_conversion_with_fixed_point_type)
6227 << DestTy;
6228 return CK_IntegralCast;
6229 case Type::STK_CPointer:
6230 case Type::STK_ObjCObjectPointer:
6231 case Type::STK_BlockPointer:
6232 case Type::STK_MemberPointer:
6233 llvm_unreachable("illegal cast to pointer type");
6234 }
6235 llvm_unreachable("Should have returned before this");
6236
6237 case Type::STK_Bool: // casting from bool is like casting from an integer
6238 case Type::STK_Integral:
6239 switch (DestTy->getScalarTypeKind()) {
6240 case Type::STK_CPointer:
6241 case Type::STK_ObjCObjectPointer:
6242 case Type::STK_BlockPointer:
6243 if (Src.get()->isNullPointerConstant(Context,
6244 Expr::NPC_ValueDependentIsNull))
6245 return CK_NullToPointer;
6246 return CK_IntegralToPointer;
6247 case Type::STK_Bool:
6248 return CK_IntegralToBoolean;
6249 case Type::STK_Integral:
6250 return CK_IntegralCast;
6251 case Type::STK_Floating:
6252 return CK_IntegralToFloating;
6253 case Type::STK_IntegralComplex:
6254 Src = ImpCastExprToType(Src.get(),
6255 DestTy->castAs<ComplexType>()->getElementType(),
6256 CK_IntegralCast);
6257 return CK_IntegralRealToComplex;
6258 case Type::STK_FloatingComplex:
6259 Src = ImpCastExprToType(Src.get(),
6260 DestTy->castAs<ComplexType>()->getElementType(),
6261 CK_IntegralToFloating);
6262 return CK_FloatingRealToComplex;
6263 case Type::STK_MemberPointer:
6264 llvm_unreachable("member pointer type in C");
6265 case Type::STK_FixedPoint:
6266 return CK_IntegralToFixedPoint;
6267 }
6268 llvm_unreachable("Should have returned before this");
6269
6270 case Type::STK_Floating:
6271 switch (DestTy->getScalarTypeKind()) {
6272 case Type::STK_Floating:
6273 return CK_FloatingCast;
6274 case Type::STK_Bool:
6275 return CK_FloatingToBoolean;
6276 case Type::STK_Integral:
6277 return CK_FloatingToIntegral;
6278 case Type::STK_FloatingComplex:
6279 Src = ImpCastExprToType(Src.get(),
6280 DestTy->castAs<ComplexType>()->getElementType(),
6281 CK_FloatingCast);
6282 return CK_FloatingRealToComplex;
6283 case Type::STK_IntegralComplex:
6284 Src = ImpCastExprToType(Src.get(),
6285 DestTy->castAs<ComplexType>()->getElementType(),
6286 CK_FloatingToIntegral);
6287 return CK_IntegralRealToComplex;
6288 case Type::STK_CPointer:
6289 case Type::STK_ObjCObjectPointer:
6290 case Type::STK_BlockPointer:
6291 llvm_unreachable("valid float->pointer cast?");
6292 case Type::STK_MemberPointer:
6293 llvm_unreachable("member pointer type in C");
6294 case Type::STK_FixedPoint:
6295 Diag(Src.get()->getExprLoc(),
6296 diag::err_unimplemented_conversion_with_fixed_point_type)
6297 << SrcTy;
6298 return CK_IntegralCast;
6299 }
6300 llvm_unreachable("Should have returned before this");
6301
6302 case Type::STK_FloatingComplex:
6303 switch (DestTy->getScalarTypeKind()) {
6304 case Type::STK_FloatingComplex:
6305 return CK_FloatingComplexCast;
6306 case Type::STK_IntegralComplex:
6307 return CK_FloatingComplexToIntegralComplex;
6308 case Type::STK_Floating: {
6309 QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
6310 if (Context.hasSameType(ET, DestTy))
6311 return CK_FloatingComplexToReal;
6312 Src = ImpCastExprToType(Src.get(), ET, CK_FloatingComplexToReal);
6313 return CK_FloatingCast;
6314 }
6315 case Type::STK_Bool:
6316 return CK_FloatingComplexToBoolean;
6317 case Type::STK_Integral:
6318 Src = ImpCastExprToType(Src.get(),
6319 SrcTy->castAs<ComplexType>()->getElementType(),
6320 CK_FloatingComplexToReal);
6321 return CK_FloatingToIntegral;
6322 case Type::STK_CPointer:
6323 case Type::STK_ObjCObjectPointer:
6324 case Type::STK_BlockPointer:
6325 llvm_unreachable("valid complex float->pointer cast?");
6326 case Type::STK_MemberPointer:
6327 llvm_unreachable("member pointer type in C");
6328 case Type::STK_FixedPoint:
6329 Diag(Src.get()->getExprLoc(),
6330 diag::err_unimplemented_conversion_with_fixed_point_type)
6331 << SrcTy;
6332 return CK_IntegralCast;
6333 }
6334 llvm_unreachable("Should have returned before this");
6335
6336 case Type::STK_IntegralComplex:
6337 switch (DestTy->getScalarTypeKind()) {
6338 case Type::STK_FloatingComplex:
6339 return CK_IntegralComplexToFloatingComplex;
6340 case Type::STK_IntegralComplex:
6341 return CK_IntegralComplexCast;
6342 case Type::STK_Integral: {
6343 QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
6344 if (Context.hasSameType(ET, DestTy))
6345 return CK_IntegralComplexToReal;
6346 Src = ImpCastExprToType(Src.get(), ET, CK_IntegralComplexToReal);
6347 return CK_IntegralCast;
6348 }
6349 case Type::STK_Bool:
6350 return CK_IntegralComplexToBoolean;
6351 case Type::STK_Floating:
6352 Src = ImpCastExprToType(Src.get(),
6353 SrcTy->castAs<ComplexType>()->getElementType(),
6354 CK_IntegralComplexToReal);
6355 return CK_IntegralToFloating;
6356 case Type::STK_CPointer:
6357 case Type::STK_ObjCObjectPointer:
6358 case Type::STK_BlockPointer:
6359 llvm_unreachable("valid complex int->pointer cast?");
6360 case Type::STK_MemberPointer:
6361 llvm_unreachable("member pointer type in C");
6362 case Type::STK_FixedPoint:
6363 Diag(Src.get()->getExprLoc(),
6364 diag::err_unimplemented_conversion_with_fixed_point_type)
6365 << SrcTy;
6366 return CK_IntegralCast;
6367 }
6368 llvm_unreachable("Should have returned before this");
6369 }
6370
6371 llvm_unreachable("Unhandled scalar cast");
6372}
6373
6374static bool breakDownVectorType(QualType type, uint64_t &len,
6375 QualType &eltType) {
6376 // Vectors are simple.
6377 if (const VectorType *vecType = type->getAs<VectorType>()) {
6378 len = vecType->getNumElements();
6379 eltType = vecType->getElementType();
6380 assert(eltType->isScalarType());
6381 return true;
6382 }
6383
6384 // We allow lax conversion to and from non-vector types, but only if
6385 // they're real types (i.e. non-complex, non-pointer scalar types).
6386 if (!type->isRealType()) return false;
6387
6388 len = 1;
6389 eltType = type;
6390 return true;
6391}
6392
6393/// Are the two types lax-compatible vector types? That is, given
6394/// that one of them is a vector, do they have equal storage sizes,
6395/// where the storage size is the number of elements times the element
6396/// size?
6397///
6398/// This will also return false if either of the types is neither a
6399/// vector nor a real type.
6400bool Sema::areLaxCompatibleVectorTypes(QualType srcTy, QualType destTy) {
6401 assert(destTy->isVectorType() || srcTy->isVectorType());
6402
6403 // Disallow lax conversions between scalars and ExtVectors (these
6404 // conversions are allowed for other vector types because common headers
6405 // depend on them). Most scalar OP ExtVector cases are handled by the
6406 // splat path anyway, which does what we want (convert, not bitcast).
6407 // What this rules out for ExtVectors is crazy things like char4*float.
6408 if (srcTy->isScalarType() && destTy->isExtVectorType()) return false;
6409 if (destTy->isScalarType() && srcTy->isExtVectorType()) return false;
6410
6411 uint64_t srcLen, destLen;
6412 QualType srcEltTy, destEltTy;
6413 if (!breakDownVectorType(srcTy, srcLen, srcEltTy)) return false;
6414 if (!breakDownVectorType(destTy, destLen, destEltTy)) return false;
6415
6416 // ASTContext::getTypeSize will return the size rounded up to a
6417 // power of 2, so instead of using that, we need to use the raw
6418 // element size multiplied by the element count.
6419 uint64_t srcEltSize = Context.getTypeSize(srcEltTy);
6420 uint64_t destEltSize = Context.getTypeSize(destEltTy);
6421
6422 return (srcLen * srcEltSize == destLen * destEltSize);
6423}
6424
6425/// Is this a legal conversion between two types, one of which is
6426/// known to be a vector type?
6427bool Sema::isLaxVectorConversion(QualType srcTy, QualType destTy) {
6428 assert(destTy->isVectorType() || srcTy->isVectorType());
6429
6430 if (!Context.getLangOpts().LaxVectorConversions)
6431 return false;
6432 return areLaxCompatibleVectorTypes(srcTy, destTy);
6433}
6434
6435bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
6436 CastKind &Kind) {
6437 assert(VectorTy->isVectorType() && "Not a vector type!");
6438
6439 if (Ty->isVectorType() || Ty->isIntegralType(Context)) {
6440 if (!areLaxCompatibleVectorTypes(Ty, VectorTy))
6441 return Diag(R.getBegin(),
6442 Ty->isVectorType() ?
6443 diag::err_invalid_conversion_between_vectors :
6444 diag::err_invalid_conversion_between_vector_and_integer)
6445 << VectorTy << Ty << R;
6446 } else
6447 return Diag(R.getBegin(),
6448 diag::err_invalid_conversion_between_vector_and_scalar)
6449 << VectorTy << Ty << R;
6450
6451 Kind = CK_BitCast;
6452 return false;
6453}
6454
6455ExprResult Sema::prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr) {
6456 QualType DestElemTy = VectorTy->castAs<VectorType>()->getElementType();
6457
6458 if (DestElemTy == SplattedExpr->getType())
6459 return SplattedExpr;
6460
6461 assert(DestElemTy->isFloatingType() ||
6462 DestElemTy->isIntegralOrEnumerationType());
6463
6464 CastKind CK;
6465 if (VectorTy->isExtVectorType() && SplattedExpr->getType()->isBooleanType()) {
6466 // OpenCL requires that we convert `true` boolean expressions to -1, but
6467 // only when splatting vectors.
6468 if (DestElemTy->isFloatingType()) {
6469 // To avoid having to have a CK_BooleanToSignedFloating cast kind, we cast
6470 // in two steps: boolean to signed integral, then to floating.
6471 ExprResult CastExprRes = ImpCastExprToType(SplattedExpr, Context.IntTy,
6472 CK_BooleanToSignedIntegral);
6473 SplattedExpr = CastExprRes.get();
6474 CK = CK_IntegralToFloating;
6475 } else {
6476 CK = CK_BooleanToSignedIntegral;
6477 }
6478 } else {
6479 ExprResult CastExprRes = SplattedExpr;
6480 CK = PrepareScalarCast(CastExprRes, DestElemTy);
6481 if (CastExprRes.isInvalid())
6482 return ExprError();
6483 SplattedExpr = CastExprRes.get();
6484 }
6485 return ImpCastExprToType(SplattedExpr, DestElemTy, CK);
6486}
6487
6488ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy,
6489 Expr *CastExpr, CastKind &Kind) {
6490 assert(DestTy->isExtVectorType() && "Not an extended vector type!");
6491
6492 QualType SrcTy = CastExpr->getType();
6493
6494 // If SrcTy is a VectorType, the total size must match to explicitly cast to
6495 // an ExtVectorType.
6496 // In OpenCL, casts between vectors of different types are not allowed.
6497 // (See OpenCL 6.2).
6498 if (SrcTy->isVectorType()) {
6499 if (!areLaxCompatibleVectorTypes(SrcTy, DestTy) ||
6500 (getLangOpts().OpenCL &&
6501 !Context.hasSameUnqualifiedType(DestTy, SrcTy))) {
6502 Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors)
6503 << DestTy << SrcTy << R;
6504 return ExprError();
6505 }
6506 Kind = CK_BitCast;
6507 return CastExpr;
6508 }
6509
6510 // All non-pointer scalars can be cast to ExtVector type. The appropriate
6511 // conversion will take place first from scalar to elt type, and then
6512 // splat from elt type to vector.
6513 if (SrcTy->isPointerType())
6514 return Diag(R.getBegin(),
6515 diag::err_invalid_conversion_between_vector_and_scalar)
6516 << DestTy << SrcTy << R;
6517
6518 Kind = CK_VectorSplat;
6519 return prepareVectorSplat(DestTy, CastExpr);
6520}
6521
6522ExprResult
6523Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
6524 Declarator &D, ParsedType &Ty,
6525 SourceLocation RParenLoc, Expr *CastExpr) {
6526 assert(!D.isInvalidType() && (CastExpr != nullptr) &&
6527 "ActOnCastExpr(): missing type or expr");
6528
6529 TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType());
6530 if (D.isInvalidType())
6531 return ExprError();
6532
6533 if (getLangOpts().CPlusPlus) {
6534 // Check that there are no default arguments (C++ only).
6535 CheckExtraCXXDefaultArguments(D);
6536 } else {
6537 // Make sure any TypoExprs have been dealt with.
6538 ExprResult Res = CorrectDelayedTyposInExpr(CastExpr);
6539 if (!Res.isUsable())
6540 return ExprError();
6541 CastExpr = Res.get();
6542 }
6543
6544 checkUnusedDeclAttributes(D);
6545
6546 QualType castType = castTInfo->getType();
6547 Ty = CreateParsedType(castType, castTInfo);
6548
6549 bool isVectorLiteral = false;
6550
6551 // Check for an altivec or OpenCL literal,
6552 // i.e. all the elements are integer constants.
6553 ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr);
6554 ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr);
6555 if ((getLangOpts().AltiVec || getLangOpts().ZVector || getLangOpts().OpenCL)
6556 && castType->isVectorType() && (PE || PLE)) {
6557 if (PLE && PLE->getNumExprs() == 0) {
6558 Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer);
6559 return ExprError();
6560 }
6561 if (PE || PLE->getNumExprs() == 1) {
6562 Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0));
6563 if (!E->getType()->isVectorType())
6564 isVectorLiteral = true;
6565 }
6566 else
6567 isVectorLiteral = true;
6568 }
6569
6570 // If this is a vector initializer, '(' type ')' '(' init, ..., init ')'
6571 // then handle it as such.
6572 if (isVectorLiteral)
6573 return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo);
6574
6575 // If the Expr being casted is a ParenListExpr, handle it specially.
6576 // This is not an AltiVec-style cast, so turn the ParenListExpr into a
6577 // sequence of BinOp comma operators.
6578 if (isa<ParenListExpr>(CastExpr)) {
6579 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr);
6580 if (Result.isInvalid()) return ExprError();
6581 CastExpr = Result.get();
6582 }
6583
6584 if (getLangOpts().CPlusPlus && !castType->isVoidType() &&
6585 !getSourceManager().isInSystemMacro(LParenLoc))
6586 Diag(LParenLoc, diag::warn_old_style_cast) << CastExpr->getSourceRange();
6587
6588 CheckTollFreeBridgeCast(castType, CastExpr);
6589
6590 CheckObjCBridgeRelatedCast(castType, CastExpr);
6591
6592 DiscardMisalignedMemberAddress(castType.getTypePtr(), CastExpr);
6593
6594 return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr);
6595}
6596
6597ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc,
6598 SourceLocation RParenLoc, Expr *E,
6599 TypeSourceInfo *TInfo) {
6600 assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) &&
6601 "Expected paren or paren list expression");
6602
6603 Expr **exprs;
6604 unsigned numExprs;
6605 Expr *subExpr;
6606 SourceLocation LiteralLParenLoc, LiteralRParenLoc;
6607 if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) {
6608 LiteralLParenLoc = PE->getLParenLoc();
6609 LiteralRParenLoc = PE->getRParenLoc();
6610 exprs = PE->getExprs();
6611 numExprs = PE->getNumExprs();
6612 } else { // isa<ParenExpr> by assertion at function entrance
6613 LiteralLParenLoc = cast<ParenExpr>(E)->getLParen();
6614 LiteralRParenLoc = cast<ParenExpr>(E)->getRParen();
6615 subExpr = cast<ParenExpr>(E)->getSubExpr();
6616 exprs = &subExpr;
6617 numExprs = 1;
6618 }
6619
6620 QualType Ty = TInfo->getType();
6621 assert(Ty->isVectorType() && "Expected vector type");
6622
6623 SmallVector<Expr *, 8> initExprs;
6624 const VectorType *VTy = Ty->getAs<VectorType>();
6625 unsigned numElems = Ty->getAs<VectorType>()->getNumElements();
6626
6627 // '(...)' form of vector initialization in AltiVec: the number of
6628 // initializers must be one or must match the size of the vector.
6629 // If a single value is specified in the initializer then it will be
6630 // replicated to all the components of the vector
6631 if (VTy->getVectorKind() == VectorType::AltiVecVector) {
6632 // The number of initializers must be one or must match the size of the
6633 // vector. If a single value is specified in the initializer then it will
6634 // be replicated to all the components of the vector
6635 if (numExprs == 1) {
6636 QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
6637 ExprResult Literal = DefaultLvalueConversion(exprs[0]);
6638 if (Literal.isInvalid())
6639 return ExprError();
6640 Literal = ImpCastExprToType(Literal.get(), ElemTy,
6641 PrepareScalarCast(Literal, ElemTy));
6642 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
6643 }
6644 else if (numExprs < numElems) {
6645 Diag(E->getExprLoc(),
6646 diag::err_incorrect_number_of_vector_initializers);
6647 return ExprError();
6648 }
6649 else
6650 initExprs.append(exprs, exprs + numExprs);
6651 }
6652 else {
6653 // For OpenCL, when the number of initializers is a single value,
6654 // it will be replicated to all components of the vector.
6655 if (getLangOpts().OpenCL &&
6656 VTy->getVectorKind() == VectorType::GenericVector &&
6657 numExprs == 1) {
6658 QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
6659 ExprResult Literal = DefaultLvalueConversion(exprs[0]);
6660 if (Literal.isInvalid())
6661 return ExprError();
6662 Literal = ImpCastExprToType(Literal.get(), ElemTy,
6663 PrepareScalarCast(Literal, ElemTy));
6664 return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
6665 }
6666
6667 initExprs.append(exprs, exprs + numExprs);
6668 }
6669 // FIXME: This means that pretty-printing the final AST will produce curly
6670 // braces instead of the original commas.
6671 InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc,
6672 initExprs, LiteralRParenLoc);
6673 initE->setType(Ty);
6674 return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE);
6675}
6676
6677/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn
6678/// the ParenListExpr into a sequence of comma binary operators.
6679ExprResult
6680Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) {
6681 ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr);
6682 if (!E)
6683 return OrigExpr;
6684
6685 ExprResult Result(E->getExpr(0));
6686
6687 for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
6688 Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(),
6689 E->getExpr(i));
6690
6691 if (Result.isInvalid()) return ExprError();
6692
6693 return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get());
6694}
6695
6696ExprResult Sema::ActOnParenListExpr(SourceLocation L,
6697 SourceLocation R,
6698 MultiExprArg Val) {
6699 return ParenListExpr::Create(Context, L, Val, R);
6700}
6701
6702/// Emit a specialized diagnostic when one expression is a null pointer
6703/// constant and the other is not a pointer. Returns true if a diagnostic is
6704/// emitted.
6705bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr,
6706 SourceLocation QuestionLoc) {
6707 Expr *NullExpr = LHSExpr;
6708 Expr *NonPointerExpr = RHSExpr;
6709 Expr::NullPointerConstantKind NullKind =
6710 NullExpr->isNullPointerConstant(Context,
6711 Expr::NPC_ValueDependentIsNotNull);
6712
6713 if (NullKind == Expr::NPCK_NotNull) {
6714 NullExpr = RHSExpr;
6715 NonPointerExpr = LHSExpr;
6716 NullKind =
6717 NullExpr->isNullPointerConstant(Context,
6718 Expr::NPC_ValueDependentIsNotNull);
6719 }
6720
6721 if (NullKind == Expr::NPCK_NotNull)
6722 return false;
6723
6724 if (NullKind == Expr::NPCK_ZeroExpression)
6725 return false;
6726
6727 if (NullKind == Expr::NPCK_ZeroLiteral) {
6728 // In this case, check to make sure that we got here from a "NULL"
6729 // string in the source code.
6730 NullExpr = NullExpr->IgnoreParenImpCasts();
6731 SourceLocation loc = NullExpr->getExprLoc();
6732 if (!findMacroSpelling(loc, "NULL"))
6733 return false;
6734 }
6735
6736 int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr);
6737 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null)
6738 << NonPointerExpr->getType() << DiagType
6739 << NonPointerExpr->getSourceRange();
6740 return true;
6741}
6742
6743/// Return false if the condition expression is valid, true otherwise.
6744static bool checkCondition(Sema &S, Expr *Cond, SourceLocation QuestionLoc) {
6745 QualType CondTy = Cond->getType();
6746
6747 // OpenCL v1.1 s6.3.i says the condition cannot be a floating point type.
6748 if (S.getLangOpts().OpenCL && CondTy->isFloatingType()) {
6749 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
6750 << CondTy << Cond->getSourceRange();
6751 return true;
6752 }
6753
6754 // C99 6.5.15p2
6755 if (CondTy->isScalarType()) return false;
6756
6757 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_scalar)
6758 << CondTy << Cond->getSourceRange();
6759 return true;
6760}
6761
6762/// Handle when one or both operands are void type.
6763static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS,
6764 ExprResult &RHS) {
6765 Expr *LHSExpr = LHS.get();
6766 Expr *RHSExpr = RHS.get();
6767
6768 if (!LHSExpr->getType()->isVoidType())
6769 S.Diag(RHSExpr->getBeginLoc(), diag::ext_typecheck_cond_one_void)
6770 << RHSExpr->getSourceRange();
6771 if (!RHSExpr->getType()->isVoidType())
6772 S.Diag(LHSExpr->getBeginLoc(), diag::ext_typecheck_cond_one_void)
6773 << LHSExpr->getSourceRange();
6774 LHS = S.ImpCastExprToType(LHS.get(), S.Context.VoidTy, CK_ToVoid);
6775 RHS = S.ImpCastExprToType(RHS.get(), S.Context.VoidTy, CK_ToVoid);
6776 return S.Context.VoidTy;
6777}
6778
6779/// Return false if the NullExpr can be promoted to PointerTy,
6780/// true otherwise.
6781static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr,
6782 QualType PointerTy) {
6783 if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) ||
6784 !NullExpr.get()->isNullPointerConstant(S.Context,
6785 Expr::NPC_ValueDependentIsNull))
6786 return true;
6787
6788 NullExpr = S.ImpCastExprToType(NullExpr.get(), PointerTy, CK_NullToPointer);
6789 return false;
6790}
6791
6792/// Checks compatibility between two pointers and return the resulting
6793/// type.
6794static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
6795 ExprResult &RHS,
6796 SourceLocation Loc) {
6797 QualType LHSTy = LHS.get()->getType();
6798 QualType RHSTy = RHS.get()->getType();
6799
6800 if (S.Context.hasSameType(LHSTy, RHSTy)) {
6801 // Two identical pointers types are always compatible.
6802 return LHSTy;
6803 }
6804
6805 QualType lhptee, rhptee;
6806
6807 // Get the pointee types.
6808 bool IsBlockPointer = false;
6809 if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) {
6810 lhptee = LHSBTy->getPointeeType();
6811 rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType();
6812 IsBlockPointer = true;
6813 } else {
6814 lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
6815 rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
6816 }
6817
6818 // C99 6.5.15p6: If both operands are pointers to compatible types or to
6819 // differently qualified versions of compatible types, the result type is
6820 // a pointer to an appropriately qualified version of the composite
6821 // type.
6822
6823 // Only CVR-qualifiers exist in the standard, and the differently-qualified
6824 // clause doesn't make sense for our extensions. E.g. address space 2 should
6825 // be incompatible with address space 3: they may live on different devices or
6826 // anything.
6827 Qualifiers lhQual = lhptee.getQualifiers();
6828 Qualifiers rhQual = rhptee.getQualifiers();
6829
6830 LangAS ResultAddrSpace = LangAS::Default;
6831 LangAS LAddrSpace = lhQual.getAddressSpace();
6832 LangAS RAddrSpace = rhQual.getAddressSpace();
6833
6834 // OpenCL v1.1 s6.5 - Conversion between pointers to distinct address
6835 // spaces is disallowed.
6836 if (lhQual.isAddressSpaceSupersetOf(rhQual))
6837 ResultAddrSpace = LAddrSpace;
6838 else if (rhQual.isAddressSpaceSupersetOf(lhQual))
6839 ResultAddrSpace = RAddrSpace;
6840 else {
6841 S.Diag(Loc, diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
6842 << LHSTy << RHSTy << 2 << LHS.get()->getSourceRange()
6843 << RHS.get()->getSourceRange();
6844 return QualType();
6845 }
6846
6847 unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers();
6848 auto LHSCastKind = CK_BitCast, RHSCastKind = CK_BitCast;
6849 lhQual.removeCVRQualifiers();
6850 rhQual.removeCVRQualifiers();
6851
6852 // OpenCL v2.0 specification doesn't extend compatibility of type qualifiers
6853 // (C99 6.7.3) for address spaces. We assume that the check should behave in
6854 // the same manner as it's defined for CVR qualifiers, so for OpenCL two
6855 // qual types are compatible iff
6856 // * corresponded types are compatible
6857 // * CVR qualifiers are equal
6858 // * address spaces are equal
6859 // Thus for conditional operator we merge CVR and address space unqualified
6860 // pointees and if there is a composite type we return a pointer to it with
6861 // merged qualifiers.
6862 LHSCastKind =
6863 LAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
6864 RHSCastKind =
6865 RAddrSpace == ResultAddrSpace ? CK_BitCast : CK_AddressSpaceConversion;
6866 lhQual.removeAddressSpace();
6867 rhQual.removeAddressSpace();
6868
6869 lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual);
6870 rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual);
6871
6872 QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee);
6873
6874 if (CompositeTy.isNull()) {
6875 // In this situation, we assume void* type. No especially good
6876 // reason, but this is what gcc does, and we do have to pick
6877 // to get a consistent AST.
6878 QualType incompatTy;
6879 incompatTy = S.Context.getPointerType(
6880 S.Context.getAddrSpaceQualType(S.Context.VoidTy, ResultAddrSpace));
6881 LHS = S.ImpCastExprToType(LHS.get(), incompatTy, LHSCastKind);
6882 RHS = S.ImpCastExprToType(RHS.get(), incompatTy, RHSCastKind);
6883
6884 // FIXME: For OpenCL the warning emission and cast to void* leaves a room
6885 // for casts between types with incompatible address space qualifiers.
6886 // For the following code the compiler produces casts between global and
6887 // local address spaces of the corresponded innermost pointees:
6888 // local int *global *a;
6889 // global int *global *b;
6890 // a = (0 ? a : b); // see C99 6.5.16.1.p1.
6891 S.Diag(Loc, diag::ext_typecheck_cond_incompatible_pointers)
6892 << LHSTy << RHSTy << LHS.get()->getSourceRange()
6893 << RHS.get()->getSourceRange();
6894
6895 return incompatTy;
6896 }
6897
6898 // The pointer types are compatible.
6899 // In case of OpenCL ResultTy should have the address space qualifier
6900 // which is a superset of address spaces of both the 2nd and the 3rd
6901 // operands of the conditional operator.
6902 QualType ResultTy = [&, ResultAddrSpace]() {
6903 if (S.getLangOpts().OpenCL) {
6904 Qualifiers CompositeQuals = CompositeTy.getQualifiers();
6905 CompositeQuals.setAddressSpace(ResultAddrSpace);
6906 return S.Context
6907 .getQualifiedType(CompositeTy.getUnqualifiedType(), CompositeQuals)
6908 .withCVRQualifiers(MergedCVRQual);
6909 }
6910 return CompositeTy.withCVRQualifiers(MergedCVRQual);
6911 }();
6912 if (IsBlockPointer)
6913 ResultTy = S.Context.getBlockPointerType(ResultTy);
6914 else {
6915 ASTContext::PointerInterpretationKind PIK = ASTContext::PIK_Default;
6916 if (LHSTy->isCHERICapabilityType(S.Context)
6917 || RHSTy->isCHERICapabilityType(S.Context)) {
6918 PIK = ASTContext::PIK_Capability;
6919 }
6920 ResultTy = S.Context.getPointerType(ResultTy, PIK);
6921 }
6922
6923 LHS = S.ImpCastExprToType(LHS.get(), ResultTy, LHSCastKind);
6924 RHS = S.ImpCastExprToType(RHS.get(), ResultTy, RHSCastKind);
6925 return ResultTy;
6926}
6927
6928/// Return the resulting type when the operands are both block pointers.
6929static QualType checkConditionalBlockPointerCompatibility(Sema &S,
6930 ExprResult &LHS,
6931 ExprResult &RHS,
6932 SourceLocation Loc) {
6933 QualType LHSTy = LHS.get()->getType();
6934 QualType RHSTy = RHS.get()->getType();
6935
6936 if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) {
6937 if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) {
6938 QualType destType = S.Context.getPointerType(S.Context.VoidTy);
6939 LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
6940 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
6941 return destType;
6942 }
6943 S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands)
6944 << LHSTy << RHSTy << LHS.get()->getSourceRange()
6945 << RHS.get()->getSourceRange();
6946 return QualType();
6947 }
6948
6949 // We have 2 block pointer types.
6950 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
6951}
6952
6953/// Return the resulting type when the operands are both pointers.
6954static QualType
6955checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS,
6956 ExprResult &RHS,
6957 SourceLocation Loc) {
6958 // get the pointer types
6959 QualType LHSTy = LHS.get()->getType();
6960 QualType RHSTy = RHS.get()->getType();
6961
6962 // get the "pointed to" types
6963 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
6964 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
6965
6966 // Get the cast kind to use for adding qualifiers
6967 // XXXAR: There should probably be a CK_CHERICapabilityToPointer here?
6968 CastKind NopCastKind = (lhptee.getAddressSpace() == rhptee.getAddressSpace())
6969 ? CK_NoOp : CK_AddressSpaceConversion;
6970
6971 // ignore qualifiers on void (C99 6.5.15p3, clause 6)
6972 if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) {
6973 // Figure out necessary qualifiers (C99 6.5.15p6)
6974 QualType destPointee
6975 = S.Context.getQualifiedType(lhptee, rhptee.getQualifiers());
6976 QualType destType = S.Context.getPointerType(destPointee,
6977 RHSTy->isCHERICapabilityType(S.Context) ? ASTContext::PIK_Capability : ASTContext::PIK_Default);
6978 // Add qualifiers if necessary.
6979 LHS = S.ImpCastExprToType(LHS.get(), destType, NopCastKind);
6980 // Promote to void*.
6981 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
6982 return destType;
6983 }
6984 if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) {
6985 QualType destPointee
6986 = S.Context.getQualifiedType(rhptee, lhptee.getQualifiers());
6987 QualType destType = S.Context.getPointerType(destPointee,
6988 LHSTy->isCHERICapabilityType(S.Context) ? ASTContext::PIK_Capability : ASTContext::PIK_Default);
6989 // Add qualifiers if necessary.
6990 RHS = S.ImpCastExprToType(RHS.get(), destType, CK_NoOp);
6991 // Promote to void*.
6992 LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
6993 return destType;
6994 }
6995
6996 return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
6997}
6998
6999/// Return false if the first expression is not an integer and the second
7000/// expression is not a pointer, true otherwise.
7001static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int,
7002 Expr* PointerExpr, SourceLocation Loc,
7003 bool IsIntFirstExpr) {
7004 if (!PointerExpr->getType()->isPointerType() ||
7005 !Int.get()->getType()->isIntegerType())
7006 return false;
7007
7008 Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr;
7009 Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get();
7010
7011 S.Diag(Loc, diag::ext_typecheck_cond_pointer_integer_mismatch)
7012 << Expr1->getType() << Expr2->getType()
7013 << Expr1->getSourceRange() << Expr2->getSourceRange();
7014 Int = S.ImpCastExprToType(Int.get(), PointerExpr->getType(),
7015 CK_IntegralToPointer);
7016 return true;
7017}
7018
7019/// Simple conversion between integer and floating point types.
7020///
7021/// Used when handling the OpenCL conditional operator where the
7022/// condition is a vector while the other operands are scalar.
7023///
7024/// OpenCL v1.1 s6.3.i and s6.11.6 together require that the scalar
7025/// types are either integer or floating type. Between the two
7026/// operands, the type with the higher rank is defined as the "result
7027/// type". The other operand needs to be promoted to the same type. No
7028/// other type promotion is allowed. We cannot use
7029/// UsualArithmeticConversions() for this purpose, since it always
7030/// promotes promotable types.
7031static QualType OpenCLArithmeticConversions(Sema &S, ExprResult &LHS,
7032 ExprResult &RHS,
7033 SourceLocation QuestionLoc) {
7034 LHS = S.DefaultFunctionArrayLvalueConversion(LHS.get());
7035 if (LHS.isInvalid())
7036 return QualType();
7037 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
7038 if (RHS.isInvalid())
7039 return QualType();
7040
7041 // For conversion purposes, we ignore any qualifiers.
7042 // For example, "const float" and "float" are equivalent.
7043 QualType LHSType =
7044 S.Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
7045 QualType RHSType =
7046 S.Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
7047
7048 if (!LHSType->isIntegerType() && !LHSType->isRealFloatingType()) {
7049 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
7050 << LHSType << LHS.get()->getSourceRange();
7051 return QualType();
7052 }
7053
7054 if (!RHSType->isIntegerType() && !RHSType->isRealFloatingType()) {
7055 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
7056 << RHSType << RHS.get()->getSourceRange();
7057 return QualType();
7058 }
7059
7060 // If both types are identical, no conversion is needed.
7061 if (LHSType == RHSType)
7062 return LHSType;
7063
7064 // Now handle "real" floating types (i.e. float, double, long double).
7065 if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
7066 return handleFloatConversion(S, LHS, RHS, LHSType, RHSType,
7067 /*IsCompAssign = */ false);
7068
7069 // Finally, we have two differing integer types.
7070 return handleIntegerConversion<doIntegralCast, doIntegralCast>
7071 (S, LHS, RHS, LHSType, RHSType, /*IsCompAssign = */ false);
7072}
7073
7074/// Convert scalar operands to a vector that matches the
7075/// condition in length.
7076///
7077/// Used when handling the OpenCL conditional operator where the
7078/// condition is a vector while the other operands are scalar.
7079///
7080/// We first compute the "result type" for the scalar operands
7081/// according to OpenCL v1.1 s6.3.i. Both operands are then converted
7082/// into a vector of that type where the length matches the condition
7083/// vector type. s6.11.6 requires that the element types of the result
7084/// and the condition must have the same number of bits.
7085static QualType
7086OpenCLConvertScalarsToVectors(Sema &S, ExprResult &LHS, ExprResult &RHS,
7087 QualType CondTy, SourceLocation QuestionLoc) {
7088 QualType ResTy = OpenCLArithmeticConversions(S, LHS, RHS, QuestionLoc);
7089 if (ResTy.isNull()) return QualType();
7090
7091 const VectorType *CV = CondTy->getAs<VectorType>();
7092 assert(CV);
7093
7094 // Determine the vector result type
7095 unsigned NumElements = CV->getNumElements();
7096 QualType VectorTy = S.Context.getExtVectorType(ResTy, NumElements);
7097
7098 // Ensure that all types have the same number of bits
7099 if (S.Context.getTypeSize(CV->getElementType())
7100 != S.Context.getTypeSize(ResTy)) {
7101 // Since VectorTy is created internally, it does not pretty print
7102 // with an OpenCL name. Instead, we just print a description.
7103 std::string EleTyName = ResTy.getUnqualifiedType().getAsString();
7104 SmallString<64> Str;
7105 llvm::raw_svector_ostream OS(Str);
7106 OS << "(vector of " << NumElements << " '" << EleTyName << "' values)";
7107 S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
7108 << CondTy << OS.str();
7109 return QualType();
7110 }
7111
7112 // Convert operands to the vector result type
7113 LHS = S.ImpCastExprToType(LHS.get(), VectorTy, CK_VectorSplat);
7114 RHS = S.ImpCastExprToType(RHS.get(), VectorTy, CK_VectorSplat);
7115
7116 return VectorTy;
7117}
7118
7119/// Return false if this is a valid OpenCL condition vector
7120static bool checkOpenCLConditionVector(Sema &S, Expr *Cond,
7121 SourceLocation QuestionLoc) {
7122 // OpenCL v1.1 s6.11.6 says the elements of the vector must be of
7123 // integral type.
7124 const VectorType *CondTy = Cond->getType()->getAs<VectorType>();
7125 assert(CondTy);
7126 QualType EleTy = CondTy->getElementType();
7127 if (EleTy->isIntegerType()) return false;
7128
7129 S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
7130 << Cond->getType() << Cond->getSourceRange();
7131 return true;
7132}
7133
7134/// Return false if the vector condition type and the vector
7135/// result type are compatible.
7136///
7137/// OpenCL v1.1 s6.11.6 requires that both vector types have the same
7138/// number of elements, and their element types have the same number
7139/// of bits.
7140static bool checkVectorResult(Sema &S, QualType CondTy, QualType VecResTy,
7141 SourceLocation QuestionLoc) {
7142 const VectorType *CV = CondTy->getAs<VectorType>();
7143 const VectorType *RV = VecResTy->getAs<VectorType>();
7144 assert(CV && RV);
7145
7146 if (CV->getNumElements() != RV->getNumElements()) {
7147 S.Diag(QuestionLoc, diag::err_conditional_vector_size)
7148 << CondTy << VecResTy;
7149 return true;
7150 }
7151
7152 QualType CVE = CV->getElementType();
7153 QualType RVE = RV->getElementType();
7154
7155 if (S.Context.getTypeSize(CVE) != S.Context.getTypeSize(RVE)) {
7156 S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
7157 << CondTy << VecResTy;
7158 return true;
7159 }
7160
7161 return false;
7162}
7163
7164/// Return the resulting type for the conditional operator in
7165/// OpenCL (aka "ternary selection operator", OpenCL v1.1
7166/// s6.3.i) when the condition is a vector type.
7167static QualType
7168OpenCLCheckVectorConditional(Sema &S, ExprResult &Cond,
7169 ExprResult &LHS, ExprResult &RHS,
7170 SourceLocation QuestionLoc) {
7171 Cond = S.DefaultFunctionArrayLvalueConversion(Cond.get());
7172 if (Cond.isInvalid())
7173 return QualType();
7174 QualType CondTy = Cond.get()->getType();
7175
7176 if (checkOpenCLConditionVector(S, Cond.get(), QuestionLoc))
7177 return QualType();
7178
7179 // If either operand is a vector then find the vector type of the
7180 // result as specified in OpenCL v1.1 s6.3.i.
7181 if (LHS.get()->getType()->isVectorType() ||
7182 RHS.get()->getType()->isVectorType()) {
7183 QualType VecResTy = S.CheckVectorOperands(LHS, RHS, QuestionLoc,
7184 /*isCompAssign*/false,
7185 /*AllowBothBool*/true,
7186 /*AllowBoolConversions*/false);
7187 if (VecResTy.isNull()) return QualType();
7188 // The result type must match the condition type as specified in
7189 // OpenCL v1.1 s6.11.6.
7190 if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
7191 return QualType();
7192 return VecResTy;
7193 }
7194
7195 // Both operands are scalar.
7196 return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
7197}
7198
7199/// Return true if the Expr is block type
7200static bool checkBlockType(Sema &S, const Expr *E) {
7201 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
7202 QualType Ty = CE->getCallee()->getType();
7203 if (Ty->isBlockPointerType()) {
7204 S.Diag(E->getExprLoc(), diag::err_opencl_ternary_with_block);
7205 return true;
7206 }
7207 }
7208 return false;
7209}
7210
7211/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
7212/// In that case, LHS = cond.
7213/// C99 6.5.15
7214QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
7215 ExprResult &RHS, ExprValueKind &VK,
7216 ExprObjectKind &OK,
7217 SourceLocation QuestionLoc) {
7218
7219 ExprResult LHSResult = CheckPlaceholderExpr(LHS.get());
7220 if (!LHSResult.isUsable()) return QualType();
7221 LHS = LHSResult;
7222
7223 ExprResult RHSResult = CheckPlaceholderExpr(RHS.get());
7224 if (!RHSResult.isUsable()) return QualType();
7225 RHS = RHSResult;
7226
7227 // C++ is sufficiently different to merit its own checker.
7228 if (getLangOpts().CPlusPlus)
7229 return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc);
7230
7231 VK = VK_RValue;
7232 OK = OK_Ordinary;
7233
7234 // The OpenCL operator with a vector condition is sufficiently
7235 // different to merit its own checker.
7236 if (getLangOpts().OpenCL && Cond.get()->getType()->isVectorType())
7237 return OpenCLCheckVectorConditional(*this, Cond, LHS, RHS, QuestionLoc);
7238
7239 // First, check the condition.
7240 Cond = UsualUnaryConversions(Cond.get());
7241 if (Cond.isInvalid())
7242 return QualType();
7243 if (checkCondition(*this, Cond.get(), QuestionLoc))
7244 return QualType();
7245
7246 // Now check the two expressions.
7247 if (LHS.get()->getType()->isVectorType() ||
7248 RHS.get()->getType()->isVectorType())
7249 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
7250 /*AllowBothBool*/true,
7251 /*AllowBoolConversions*/false);
7252
7253 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
7254 if (LHS.isInvalid() || RHS.isInvalid())
7255 return QualType();
7256
7257 QualType LHSTy = LHS.get()->getType();
7258 QualType RHSTy = RHS.get()->getType();
7259
7260 // Diagnose attempts to convert between __float128 and long double where
7261 // such conversions currently can't be handled.
7262 if (unsupportedTypeConversion(*this, LHSTy, RHSTy)) {
7263 Diag(QuestionLoc,
7264 diag::err_typecheck_cond_incompatible_operands) << LHSTy << RHSTy
7265 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7266 return QualType();
7267 }
7268
7269 // OpenCL v2.0 s6.12.5 - Blocks cannot be used as expressions of the ternary
7270 // selection operator (?:).
7271 if (getLangOpts().OpenCL &&
7272 (checkBlockType(*this, LHS.get()) | checkBlockType(*this, RHS.get()))) {
7273 return QualType();
7274 }
7275
7276 // If both operands have arithmetic type, do the usual arithmetic conversions
7277 // to find a common type: C99 6.5.15p3,5.
7278 if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
7279 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
7280 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
7281
7282 return ResTy;
7283 }
7284
7285 // If both operands are the same structure or union type, the result is that
7286 // type.
7287 if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3
7288 if (const RecordType *RHSRT = RHSTy->getAs<RecordType>())
7289 if (LHSRT->getDecl() == RHSRT->getDecl())
7290 // "If both the operands have structure or union type, the result has
7291 // that type." This implies that CV qualifiers are dropped.
7292 return LHSTy.getUnqualifiedType();
7293 // FIXME: Type of conditional expression must be complete in C mode.
7294 }
7295
7296 // C99 6.5.15p5: "If both operands have void type, the result has void type."
7297 // The following || allows only one side to be void (a GCC-ism).
7298 if (LHSTy->isVoidType() || RHSTy->isVoidType()) {
7299 return checkConditionalVoidType(*this, LHS, RHS);
7300 }
7301
7302 // C99 6.5.15p6 - "if one operand is a null pointer constant, the result has
7303 // the type of the other operand."
7304 if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy;
7305 if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy;
7306
7307 // All objective-c pointer type analysis is done here.
7308 QualType compositeType = FindCompositeObjCPointerType(LHS, RHS,
7309 QuestionLoc);
7310 if (LHS.isInvalid() || RHS.isInvalid())
7311 return QualType();
7312 if (!compositeType.isNull())
7313 return compositeType;
7314
7315
7316 // Handle block pointer types.
7317 if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType())
7318 return checkConditionalBlockPointerCompatibility(*this, LHS, RHS,
7319 QuestionLoc);
7320
7321 // Check constraints for C object pointers types (C99 6.5.15p3,6).
7322 if (LHSTy->isPointerType() && RHSTy->isPointerType())
7323 return checkConditionalObjectPointersCompatibility(*this, LHS, RHS,
7324 QuestionLoc);
7325
7326 // GCC compatibility: soften pointer/integer mismatch. Note that
7327 // null pointers have been filtered out by this point.
7328 if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc,
7329 /*isIntFirstExpr=*/true))
7330 return RHSTy;
7331 if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc,
7332 /*isIntFirstExpr=*/false))
7333 return LHSTy;
7334
7335 // Emit a better diagnostic if one of the expressions is a null pointer
7336 // constant and the other is not a pointer type. In this case, the user most
7337 // likely forgot to take the address of the other expression.
7338 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
7339 return QualType();
7340
7341 // Otherwise, the operands are not compatible.
7342 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
7343 << LHSTy << RHSTy << LHS.get()->getSourceRange()
7344 << RHS.get()->getSourceRange();
7345 return QualType();
7346}
7347
7348/// FindCompositeObjCPointerType - Helper method to find composite type of
7349/// two objective-c pointer types of the two input expressions.
7350QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
7351 SourceLocation QuestionLoc) {
7352 QualType LHSTy = LHS.get()->getType();
7353 QualType RHSTy = RHS.get()->getType();
7354
7355 // Handle things like Class and struct objc_class*. Here we case the result
7356 // to the pseudo-builtin, because that will be implicitly cast back to the
7357 // redefinition type if an attempt is made to access its fields.
7358 if (LHSTy->isObjCClassType() &&
7359 (Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) {
7360 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
7361 return LHSTy;
7362 }
7363 if (RHSTy->isObjCClassType() &&
7364 (Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) {
7365 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
7366 return RHSTy;
7367 }
7368 // And the same for struct objc_object* / id
7369 if (LHSTy->isObjCIdType() &&
7370 (Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) {
7371 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
7372 return LHSTy;
7373 }
7374 if (RHSTy->isObjCIdType() &&
7375 (Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) {
7376 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
7377 return RHSTy;
7378 }
7379 // And the same for struct objc_selector* / SEL
7380 if (Context.isObjCSelType(LHSTy) &&
7381 (Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) {
7382 RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_BitCast);
7383 return LHSTy;
7384 }
7385 if (Context.isObjCSelType(RHSTy) &&
7386 (Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) {
7387 LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_BitCast);
7388 return RHSTy;
7389 }
7390 // Check constraints for Objective-C object pointers types.
7391 if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) {
7392
7393 if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) {
7394 // Two identical object pointer types are always compatible.
7395 return LHSTy;
7396 }
7397 const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>();
7398 const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>();
7399 QualType compositeType = LHSTy;
7400
7401 // If both operands are interfaces and either operand can be
7402 // assigned to the other, use that type as the composite
7403 // type. This allows
7404 // xxx ? (A*) a : (B*) b
7405 // where B is a subclass of A.
7406 //
7407 // Additionally, as for assignment, if either type is 'id'
7408 // allow silent coercion. Finally, if the types are
7409 // incompatible then make sure to use 'id' as the composite
7410 // type so the result is acceptable for sending messages to.
7411
7412 // FIXME: Consider unifying with 'areComparableObjCPointerTypes'.
7413 // It could return the composite type.
7414 if (!(compositeType =
7415 Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) {
7416 // Nothing more to do.
7417 } else if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) {
7418 compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy;
7419 } else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) {
7420 compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy;
7421 } else if ((LHSTy->isObjCQualifiedIdType() ||
7422 RHSTy->isObjCQualifiedIdType()) &&
7423 Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) {
7424 // Need to handle "id<xx>" explicitly.
7425 // GCC allows qualified id and any Objective-C type to devolve to
7426 // id. Currently localizing to here until clear this should be
7427 // part of ObjCQualifiedIdTypesAreCompatible.
7428 compositeType = Context.getObjCIdType();
7429 } else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) {
7430 compositeType = Context.getObjCIdType();
7431 } else {
7432 Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands)
7433 << LHSTy << RHSTy
7434 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7435 QualType incompatTy = Context.getObjCIdType();
7436 LHS = ImpCastExprToType(LHS.get(), incompatTy, CK_BitCast);
7437 RHS = ImpCastExprToType(RHS.get(), incompatTy, CK_BitCast);
7438 return incompatTy;
7439 }
7440 // The object pointer types are compatible.
7441 LHS = ImpCastExprToType(LHS.get(), compositeType, CK_BitCast);
7442 RHS = ImpCastExprToType(RHS.get(), compositeType, CK_BitCast);
7443 return compositeType;
7444 }
7445 // Check Objective-C object pointer types and 'void *'
7446 if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) {
7447 if (getLangOpts().ObjCAutoRefCount) {
7448 // ARC forbids the implicit conversion of object pointers to 'void *',
7449 // so these types are not compatible.
7450 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
7451 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7452 LHS = RHS = true;
7453 return QualType();
7454 }
7455 QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
7456 QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
7457 QualType destPointee
7458 = Context.getQualifiedType(lhptee, rhptee.getQualifiers());
7459 QualType destType = Context.getPointerType(destPointee);
7460 // Add qualifiers if necessary.
7461 LHS = ImpCastExprToType(LHS.get(), destType, CK_NoOp);
7462 // Promote to void*.
7463 RHS = ImpCastExprToType(RHS.get(), destType, CK_BitCast);
7464 return destType;
7465 }
7466 if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) {
7467 if (getLangOpts().ObjCAutoRefCount) {
7468 // ARC forbids the implicit conversion of object pointers to 'void *',
7469 // so these types are not compatible.
7470 Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
7471 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
7472 LHS = RHS = true;
7473 return QualType();
7474 }
7475 QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
7476 QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
7477 QualType destPointee
7478 = Context.getQualifiedType(rhptee, lhptee.getQualifiers());
7479 QualType destType = Context.getPointerType(destPointee);
7480 // Add qualifiers if necessary.
7481 RHS = ImpCastExprToType(RHS.get(), destType, CK_NoOp);
7482 // Promote to void*.
7483 LHS = ImpCastExprToType(LHS.get(), destType, CK_BitCast);
7484 return destType;
7485 }
7486 return QualType();
7487}
7488
7489/// SuggestParentheses - Emit a note with a fixit hint that wraps
7490/// ParenRange in parentheses.
7491static void SuggestParentheses(Sema &Self, SourceLocation Loc,
7492 const PartialDiagnostic &Note,
7493 SourceRange ParenRange) {
7494 SourceLocation EndLoc = Self.getLocForEndOfToken(ParenRange.getEnd());
7495 if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() &&
7496 EndLoc.isValid()) {
7497 Self.Diag(Loc, Note)
7498 << FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
7499 << FixItHint::CreateInsertion(EndLoc, ")");
7500 } else {
7501 // We can't display the parentheses, so just show the bare note.
7502 Self.Diag(Loc, Note) << ParenRange;
7503 }
7504}
7505
7506static bool IsArithmeticOp(BinaryOperatorKind Opc) {
7507 return BinaryOperator::isAdditiveOp(Opc) ||
7508 BinaryOperator::isMultiplicativeOp(Opc) ||
7509 BinaryOperator::isShiftOp(Opc);
7510}
7511
7512/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary
7513/// expression, either using a built-in or overloaded operator,
7514/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side
7515/// expression.
7516static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode,
7517 Expr **RHSExprs) {
7518 // Don't strip parenthesis: we should not warn if E is in parenthesis.
7519 E = E->IgnoreImpCasts();
7520 E = E->IgnoreConversionOperator();
7521 E = E->IgnoreImpCasts();
7522 if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(E)) {
7523 E = MTE->GetTemporaryExpr();
7524 E = E->IgnoreImpCasts();
7525 }
7526
7527 // Built-in binary operator.
7528 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) {
7529 if (IsArithmeticOp(OP->getOpcode())) {
7530 *Opcode = OP->getOpcode();
7531 *RHSExprs = OP->getRHS();
7532 return true;
7533 }
7534 }
7535
7536 // Overloaded operator.
7537 if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) {
7538 if (Call->getNumArgs() != 2)
7539 return false;
7540
7541 // Make sure this is really a binary operator that is safe to pass into
7542 // BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op.
7543 OverloadedOperatorKind OO = Call->getOperator();
7544 if (OO < OO_Plus || OO > OO_Arrow ||
7545 OO == OO_PlusPlus || OO == OO_MinusMinus)
7546 return false;
7547
7548 BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO);
7549 if (IsArithmeticOp(OpKind)) {
7550 *Opcode = OpKind;
7551 *RHSExprs = Call->getArg(1);
7552 return true;
7553 }
7554 }
7555
7556 return false;
7557}
7558
7559/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type
7560/// or is a logical expression such as (x==y) which has int type, but is
7561/// commonly interpreted as boolean.
7562static bool ExprLooksBoolean(Expr *E) {
7563 E = E->IgnoreParenImpCasts();
7564
7565 if (E->getType()->isBooleanType())
7566 return true;
7567 if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E))
7568 return OP->isComparisonOp() || OP->isLogicalOp();
7569 if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E))
7570 return OP->getOpcode() == UO_LNot;
7571 if (E->getType()->isPointerType())
7572 return true;
7573 // FIXME: What about overloaded operator calls returning "unspecified boolean
7574 // type"s (commonly pointer-to-members)?
7575
7576 return false;
7577}
7578
7579/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator
7580/// and binary operator are mixed in a way that suggests the programmer assumed
7581/// the conditional operator has higher precedence, for example:
7582/// "int x = a + someBinaryCondition ? 1 : 2".
7583static void DiagnoseConditionalPrecedence(Sema &Self,
7584 SourceLocation OpLoc,
7585 Expr *Condition,
7586 Expr *LHSExpr,
7587 Expr *RHSExpr) {
7588 BinaryOperatorKind CondOpcode;
7589 Expr *CondRHS;
7590
7591 if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS))
7592 return;
7593 if (!ExprLooksBoolean(CondRHS))
7594 return;
7595
7596 // The condition is an arithmetic binary expression, with a right-
7597 // hand side that looks boolean, so warn.
7598
7599 Self.Diag(OpLoc, diag::warn_precedence_conditional)
7600 << Condition->getSourceRange()
7601 << BinaryOperator::getOpcodeStr(CondOpcode);
7602
7603 SuggestParentheses(
7604 Self, OpLoc,
7605 Self.PDiag(diag::note_precedence_silence)
7606 << BinaryOperator::getOpcodeStr(CondOpcode),
7607 SourceRange(Condition->getBeginLoc(), Condition->getEndLoc()));
7608
7609 SuggestParentheses(Self, OpLoc,
7610 Self.PDiag(diag::note_precedence_conditional_first),
7611 SourceRange(CondRHS->getBeginLoc(), RHSExpr->getEndLoc()));
7612}
7613
7614/// Compute the nullability of a conditional expression.
7615static QualType computeConditionalNullability(QualType ResTy, bool IsBin,
7616 QualType LHSTy, QualType RHSTy,
7617 ASTContext &Ctx) {
7618 if (!ResTy->isAnyPointerType())
7619 return ResTy;
7620
7621 auto GetNullability = [&Ctx](QualType Ty) {
7622 Optional<NullabilityKind> Kind = Ty->getNullability(Ctx);
7623 if (Kind)
7624 return *Kind;
7625 return NullabilityKind::Unspecified;
7626 };
7627
7628 auto LHSKind = GetNullability(LHSTy), RHSKind = GetNullability(RHSTy);
7629 NullabilityKind MergedKind;
7630
7631 // Compute nullability of a binary conditional expression.
7632 if (IsBin) {
7633 if (LHSKind == NullabilityKind::NonNull)
7634 MergedKind = NullabilityKind::NonNull;
7635 else
7636 MergedKind = RHSKind;
7637 // Compute nullability of a normal conditional expression.
7638 } else {
7639 if (LHSKind == NullabilityKind::Nullable ||
7640 RHSKind == NullabilityKind::Nullable)
7641 MergedKind = NullabilityKind::Nullable;
7642 else if (LHSKind == NullabilityKind::NonNull)
7643 MergedKind = RHSKind;
7644 else if (RHSKind == NullabilityKind::NonNull)
7645 MergedKind = LHSKind;
7646 else
7647 MergedKind = NullabilityKind::Unspecified;
7648 }
7649
7650 // Return if ResTy already has the correct nullability.
7651 if (GetNullability(ResTy) == MergedKind)
7652 return ResTy;
7653
7654 // Strip all nullability from ResTy.
7655 while (ResTy->getNullability(Ctx))
7656 ResTy = ResTy.getSingleStepDesugaredType(Ctx);
7657
7658 // Create a new AttributedType with the new nullability kind.
7659 auto NewAttr = AttributedType::getNullabilityAttrKind(MergedKind);
7660 return Ctx.getAttributedType(NewAttr, ResTy, ResTy);
7661}
7662
7663/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null
7664/// in the case of a the GNU conditional expr extension.
7665ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
7666 SourceLocation ColonLoc,
7667 Expr *CondExpr, Expr *LHSExpr,
7668 Expr *RHSExpr) {
7669 if (!getLangOpts().CPlusPlus) {
7670 // C cannot handle TypoExpr nodes in the condition because it
7671 // doesn't handle dependent types properly, so make sure any TypoExprs have
7672 // been dealt with before checking the operands.
7673 ExprResult CondResult = CorrectDelayedTyposInExpr(CondExpr);
7674 ExprResult LHSResult = CorrectDelayedTyposInExpr(LHSExpr);
7675 ExprResult RHSResult = CorrectDelayedTyposInExpr(RHSExpr);
7676
7677 if (!CondResult.isUsable())
7678 return ExprError();
7679
7680 if (LHSExpr) {
7681 if (!LHSResult.isUsable())
7682 return ExprError();
7683 }
7684
7685 if (!RHSResult.isUsable())
7686 return ExprError();
7687
7688 CondExpr = CondResult.get();
7689 LHSExpr = LHSResult.get();
7690 RHSExpr = RHSResult.get();
7691 }
7692
7693 // If this is the gnu "x ?: y" extension, analyze the types as though the LHS
7694 // was the condition.
7695 OpaqueValueExpr *opaqueValue = nullptr;
7696 Expr *commonExpr = nullptr;
7697 if (!LHSExpr) {
7698 commonExpr = CondExpr;
7699 // Lower out placeholder types first. This is important so that we don't
7700 // try to capture a placeholder. This happens in few cases in C++; such
7701 // as Objective-C++'s dictionary subscripting syntax.
7702 if (commonExpr->hasPlaceholderType()) {
7703 ExprResult result = CheckPlaceholderExpr(commonExpr);
7704 if (!result.isUsable()) return ExprError();
7705 commonExpr = result.get();
7706 }
7707 // We usually want to apply unary conversions *before* saving, except
7708 // in the special case of a C++ l-value conditional.
7709 if (!(getLangOpts().CPlusPlus
7710 && !commonExpr->isTypeDependent()
7711 && commonExpr->getValueKind() == RHSExpr->getValueKind()
7712 && commonExpr->isGLValue()
7713 && commonExpr->isOrdinaryOrBitFieldObject()
7714 && RHSExpr->isOrdinaryOrBitFieldObject()
7715 && Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) {
7716 ExprResult commonRes = UsualUnaryConversions(commonExpr);
7717 if (commonRes.isInvalid())
7718 return ExprError();
7719 commonExpr = commonRes.get();
7720 }
7721
7722 // If the common expression is a class or array prvalue, materialize it
7723 // so that we can safely refer to it multiple times.
7724 if (commonExpr->isRValue() && (commonExpr->getType()->isRecordType() ||
7725 commonExpr->getType()->isArrayType())) {
7726 ExprResult MatExpr = TemporaryMaterializationConversion(commonExpr);
7727 if (MatExpr.isInvalid())
7728 return ExprError();
7729 commonExpr = MatExpr.get();
7730 }
7731
7732 opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(),
7733 commonExpr->getType(),
7734 commonExpr->getValueKind(),
7735 commonExpr->getObjectKind(),
7736 commonExpr);
7737 LHSExpr = CondExpr = opaqueValue;
7738 }
7739
7740 QualType LHSTy = LHSExpr->getType(), RHSTy = RHSExpr->getType();
7741 ExprValueKind VK = VK_RValue;
7742 ExprObjectKind OK = OK_Ordinary;
7743 ExprResult Cond = CondExpr, LHS = LHSExpr, RHS = RHSExpr;
7744 QualType result = CheckConditionalOperands(Cond, LHS, RHS,
7745 VK, OK, QuestionLoc);
7746 if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() ||
7747 RHS.isInvalid())
7748 return ExprError();
7749
7750 DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(),
7751 RHS.get());
7752
7753 CheckBoolLikeConversion(Cond.get(), QuestionLoc);
7754
7755 result = computeConditionalNullability(result, commonExpr, LHSTy, RHSTy,
7756 Context);
7757
7758 if (!commonExpr)
7759 return new (Context)
7760 ConditionalOperator(Cond.get(), QuestionLoc, LHS.get(), ColonLoc,
7761 RHS.get(), result, VK, OK);
7762
7763 return new (Context) BinaryConditionalOperator(
7764 commonExpr, opaqueValue, Cond.get(), LHS.get(), RHS.get(), QuestionLoc,
7765 ColonLoc, result, VK, OK);
7766}
7767
7768// checkPointerTypesForAssignment - This is a very tricky routine (despite
7769// being closely modeled after the C99 spec:-). The odd characteristic of this
7770// routine is it effectively iqnores the qualifiers on the top level pointee.
7771// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
7772// FIXME: add a couple examples in this comment.
7773static Sema::AssignConvertType
7774checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) {
7775 assert(LHSType.isCanonical() && "LHS not canonicalized!");
7776 assert(RHSType.isCanonical() && "RHS not canonicalized!");
7777
7778 // get the "pointed to" type (ignoring qualifiers at the top level)
7779 const Type *lhptee, *rhptee;
7780 Qualifiers lhq, rhq;
7781 std::tie(lhptee, lhq) =
7782 cast<PointerType>(LHSType)->getPointeeType().split().asPair();
7783 std::tie(rhptee, rhq) =
7784 cast<PointerType>(RHSType)->getPointeeType().split().asPair();
7785
7786 Sema::AssignConvertType ConvTy = Sema::Compatible;
7787
7788 // C99 6.5.16.1p1: This following citation is common to constraints
7789 // 3 & 4 (below). ...and the type *pointed to* by the left has all the
7790 // qualifiers of the type *pointed to* by the right;
7791
7792 // As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay.
7793 if (lhq.getObjCLifetime() != rhq.getObjCLifetime() &&
7794 lhq.compatiblyIncludesObjCLifetime(rhq)) {
7795 // Ignore lifetime for further calculation.
7796 lhq.removeObjCLifetime();
7797 rhq.removeObjCLifetime();
7798 }
7799
7800 if (!lhq.compatiblyIncludes(rhq)) {
7801 // Treat address-space mismatches as fatal.
7802 if (!lhq.isAddressSpaceSupersetOf(rhq))
7803 return Sema::IncompatiblePointerDiscardsQualifiers;
7804
7805 // It's okay to add or remove GC or lifetime qualifiers when converting to
7806 // and from void*.
7807 else if (lhq.withoutObjCGCAttr().withoutObjCLifetime()
7808 .compatiblyIncludes(
7809 rhq.withoutObjCGCAttr().withoutObjCLifetime())
7810 && (lhptee->isVoidType() || rhptee->isVoidType()))
7811 ; // keep old
7812
7813 // Treat lifetime mismatches as fatal.
7814 else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
7815 ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
7816
7817 // For GCC/MS compatibility, other qualifier mismatches are treated
7818 // as still compatible in C.
7819 else ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
7820 }
7821
7822 // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
7823 // incomplete type and the other is a pointer to a qualified or unqualified
7824 // version of void...
7825 if (lhptee->isVoidType()) {
7826 if (rhptee->isIncompleteOrObjectType())
7827 return ConvTy;
7828
7829 // As an extension, we allow cast to/from void* to function pointer.
7830 assert(rhptee->isFunctionType());
7831 return Sema::FunctionVoidPointer;
7832 }
7833
7834 if (rhptee->isVoidType()) {
7835 if (lhptee->isIncompleteOrObjectType())
7836 return ConvTy;
7837
7838 // As an extension, we allow cast to/from void* to function pointer.
7839 assert(lhptee->isFunctionType());
7840 return Sema::FunctionVoidPointer;
7841 }
7842
7843 // C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
7844 // unqualified versions of compatible types, ...
7845 QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0);
7846 if (!S.Context.typesAreCompatible(ltrans, rtrans)) {
7847 // Check if the pointee types are compatible ignoring the sign.
7848 // We explicitly check for char so that we catch "char" vs
7849 // "unsigned char" on systems where "char" is unsigned.
7850 if (lhptee->isCharType())
7851 ltrans = S.Context.UnsignedCharTy;
7852 else if (lhptee->hasSignedIntegerRepresentation())
7853 ltrans = S.Context.getCorrespondingUnsignedType(ltrans);
7854
7855 if (rhptee->isCharType())
7856 rtrans = S.Context.UnsignedCharTy;
7857 else if (rhptee->hasSignedIntegerRepresentation())
7858 rtrans = S.Context.getCorrespondingUnsignedType(rtrans);
7859
7860 if (ltrans == rtrans) {
7861 // Types are compatible ignoring the sign. Qualifier incompatibility
7862 // takes priority over sign incompatibility because the sign
7863 // warning can be disabled.
7864 if (ConvTy != Sema::Compatible)
7865 return ConvTy;
7866
7867 return Sema::IncompatiblePointerSign;
7868 }
7869
7870 // If we are a multi-level pointer, it's possible that our issue is simply
7871 // one of qualification - e.g. char ** -> const char ** is not allowed. If
7872 // the eventual target type is the same and the pointers have the same
7873 // level of indirection, this must be the issue.
7874 if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) {
7875 do {
7876 std::tie(lhptee, lhq) =
7877 cast<PointerType>(lhptee)->getPointeeType().split().asPair();
7878 std::tie(rhptee, rhq) =
7879 cast<PointerType>(rhptee)->getPointeeType().split().asPair();
7880
7881 // Inconsistent address spaces at this point is invalid, even if the
7882 // address spaces would be compatible.
7883 // FIXME: This doesn't catch address space mismatches for pointers of
7884 // different nesting levels, like:
7885 // __local int *** a;
7886 // int ** b = a;
7887 // It's not clear how to actually determine when such pointers are
7888 // invalidly incompatible.
7889 if (lhq.getAddressSpace() != rhq.getAddressSpace())
7890 return Sema::IncompatibleNestedPointerAddressSpaceMismatch;
7891
7892 } while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee));
7893
7894 if (lhptee == rhptee)
7895 return Sema::IncompatibleNestedPointerQualifiers;
7896 }
7897
7898 // General pointer incompatibility takes priority over qualifiers.
7899 return Sema::IncompatiblePointer;
7900 }
7901 if (!S.getLangOpts().CPlusPlus &&
7902 S.IsFunctionConversion(ltrans, rtrans, ltrans))
7903 return Sema::IncompatiblePointer;
7904 return ConvTy;
7905}
7906
7907/// checkBlockPointerTypesForAssignment - This routine determines whether two
7908/// block pointer types are compatible or whether a block and normal pointer
7909/// are compatible. It is more restrict than comparing two function pointer
7910// types.
7911static Sema::AssignConvertType
7912checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType,
7913 QualType RHSType) {
7914 assert(LHSType.isCanonical() && "LHS not canonicalized!");
7915 assert(RHSType.isCanonical() && "RHS not canonicalized!");
7916
7917 QualType lhptee, rhptee;
7918
7919 // get the "pointed to" type (ignoring qualifiers at the top level)
7920 lhptee = cast<BlockPointerType>(LHSType)->getPointeeType();
7921 rhptee = cast<BlockPointerType>(RHSType)->getPointeeType();
7922
7923 // In C++, the types have to match exactly.
7924 if (S.getLangOpts().CPlusPlus)
7925 return Sema::IncompatibleBlockPointer;
7926
7927 Sema::AssignConvertType ConvTy = Sema::Compatible;
7928
7929 // For blocks we enforce that qualifiers are identical.
7930 Qualifiers LQuals = lhptee.getLocalQualifiers();
7931 Qualifiers RQuals = rhptee.getLocalQualifiers();
7932 if (S.getLangOpts().OpenCL) {
7933 LQuals.removeAddressSpace();
7934 RQuals.removeAddressSpace();
7935 }
7936 if (LQuals != RQuals)
7937 ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
7938
7939 // FIXME: OpenCL doesn't define the exact compile time semantics for a block
7940 // assignment.
7941 // The current behavior is similar to C++ lambdas. A block might be
7942 // assigned to a variable iff its return type and parameters are compatible
7943 // (C99 6.2.7) with the corresponding return type and parameters of the LHS of
7944 // an assignment. Presumably it should behave in way that a function pointer
7945 // assignment does in C, so for each parameter and return type:
7946 // * CVR and address space of LHS should be a superset of CVR and address
7947 // space of RHS.
7948 // * unqualified types should be compatible.
7949 if (S.getLangOpts().OpenCL) {
7950 if (!S.Context.typesAreBlockPointerCompatible(
7951 S.Context.getQualifiedType(LHSType.getUnqualifiedType(), LQuals),
7952 S.Context.getQualifiedType(RHSType.getUnqualifiedType(), RQuals)))
7953 return Sema::IncompatibleBlockPointer;
7954 } else if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType))
7955 return Sema::IncompatibleBlockPointer;
7956
7957 return ConvTy;
7958}
7959
7960/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types
7961/// for assignment compatibility.
7962static Sema::AssignConvertType
7963checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType,
7964 QualType RHSType) {
7965 assert(LHSType.isCanonical() && "LHS was not canonicalized!");
7966 assert(RHSType.isCanonical() && "RHS was not canonicalized!");
7967
7968 if (LHSType->isObjCBuiltinType()) {
7969 // Class is not compatible with ObjC object pointers.
7970 if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() &&
7971 !RHSType->isObjCQualifiedClassType())
7972 return Sema::IncompatiblePointer;
7973 return Sema::Compatible;
7974 }
7975 if (RHSType->isObjCBuiltinType()) {
7976 if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() &&
7977 !LHSType->isObjCQualifiedClassType())
7978 return Sema::IncompatiblePointer;
7979 return Sema::Compatible;
7980 }
7981 QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
7982 QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
7983
7984 if (!lhptee.isAtLeastAsQualifiedAs(rhptee) &&
7985 // make an exception for id<P>
7986 !LHSType->isObjCQualifiedIdType())
7987 return Sema::CompatiblePointerDiscardsQualifiers;
7988
7989 if (S.Context.typesAreCompatible(LHSType, RHSType))
7990 return Sema::Compatible;
7991 if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType())
7992 return Sema::IncompatibleObjCQualifiedId;
7993 return Sema::IncompatiblePointer;
7994}
7995
7996Sema::AssignConvertType
7997Sema::CheckAssignmentConstraints(SourceLocation Loc,
7998 QualType LHSType, QualType RHSType) {
7999 // Fake up an opaque expression. We don't actually care about what
8000 // cast operations are required, so if CheckAssignmentConstraints
8001 // adds casts to this they'll be wasted, but fortunately that doesn't
8002 // usually happen on valid code.
8003 OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue);
8004 ExprResult RHSPtr = &RHSExpr;
8005 CastKind K;
8006
8007 return CheckAssignmentConstraints(LHSType, RHSPtr, K, /*ConvertRHS=*/false);
8008}
8009
8010/// This helper function returns true if QT is a vector type that has element
8011/// type ElementType.
8012static bool isVector(QualType QT, QualType ElementType) {
8013 if (const VectorType *VT = QT->getAs<VectorType>())
8014 return VT->getElementType() == ElementType;
8015 return false;
8016}
8017
8018/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
8019/// has code to accommodate several GCC extensions when type checking
8020/// pointers. Here are some objectionable examples that GCC considers warnings:
8021///
8022/// int a, *pint;
8023/// short *pshort;
8024/// struct foo *pfoo;
8025///
8026/// pint = pshort; // warning: assignment from incompatible pointer type
8027/// a = pint; // warning: assignment makes integer from pointer without a cast
8028/// pint = a; // warning: assignment makes pointer from integer without a cast
8029/// pint = pfoo; // warning: assignment from incompatible pointer type
8030///
8031/// As a result, the code for dealing with pointers is more complex than the
8032/// C99 spec dictates.
8033///
8034/// Sets 'Kind' for any result kind except Incompatible.
8035Sema::AssignConvertType
8036Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
8037 CastKind &Kind, bool ConvertRHS) {
8038 QualType RHSType = RHS.get()->getType();
8039 QualType OrigLHSType = LHSType;
8040 QualType OrigRHSType = RHSType;
8041
8042 // Get canonical types. We're not formatting these types, just comparing
8043 // them.
8044 LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType();
8045 RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType();
8046
8047 // Common case: no conversion required.
8048 if (LHSType == RHSType) {
8049 Kind = CK_NoOp;
8050 return Compatible;
8051 }
8052
8053 // If we have an atomic type, try a non-atomic assignment, then just add an
8054 // atomic qualification step.
8055 if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) {
8056 Sema::AssignConvertType result =
8057 CheckAssignmentConstraints(AtomicTy->getValueType(), RHS, Kind);
8058 if (result != Compatible)
8059 return result;
8060 if (Kind != CK_NoOp && ConvertRHS)
8061 RHS = ImpCastExprToType(RHS.get(), AtomicTy->getValueType(), Kind);
8062 Kind = CK_NonAtomicToAtomic;
8063 return Compatible;
8064 }
8065
8066 // If the left-hand side is a reference type, then we are in a
8067 // (rare!) case where we've allowed the use of references in C,
8068 // e.g., as a parameter type in a built-in function. In this case,
8069 // just make sure that the type referenced is compatible with the
8070 // right-hand side type. The caller is responsible for adjusting
8071 // LHSType so that the resulting expression does not have reference
8072 // type.
8073 if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) {
8074 if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) {
8075 Kind = CK_LValueBitCast;
8076 return Compatible;
8077 }
8078 return Incompatible;
8079 }
8080
8081 // Allow scalar to ExtVector assignments, and assignments of an ExtVector type
8082 // to the same ExtVector type.
8083 if (LHSType->isExtVectorType()) {
8084 if (RHSType->isExtVectorType())
8085 return Incompatible;
8086 if (RHSType->isArithmeticType()) {
8087 // CK_VectorSplat does T -> vector T, so first cast to the element type.
8088 if (ConvertRHS)
8089 RHS = prepareVectorSplat(LHSType, RHS.get());
8090 Kind = CK_VectorSplat;
8091 return Compatible;
8092 }
8093 }
8094
8095 // Conversions to or from vector type.
8096 if (LHSType->isVectorType() || RHSType->isVectorType()) {
8097 if (LHSType->isVectorType() && RHSType->isVectorType()) {
8098 // Allow assignments of an AltiVec vector type to an equivalent GCC
8099 // vector type and vice versa
8100 if (Context.areCompatibleVectorTypes(LHSType, RHSType)) {
8101 Kind = CK_BitCast;
8102 return Compatible;
8103 }
8104
8105 // If we are allowing lax vector conversions, and LHS and RHS are both
8106 // vectors, the total size only needs to be the same. This is a bitcast;
8107 // no bits are changed but the result type is different.
8108 if (isLaxVectorConversion(RHSType, LHSType)) {
8109 Kind = CK_BitCast;
8110 return IncompatibleVectors;
8111 }
8112 }
8113
8114 // When the RHS comes from another lax conversion (e.g. binops between
8115 // scalars and vectors) the result is canonicalized as a vector. When the
8116 // LHS is also a vector, the lax is allowed by the condition above. Handle
8117 // the case where LHS is a scalar.
8118 if (LHSType->isScalarType()) {
8119 const VectorType *VecType = RHSType->getAs<VectorType>();
8120 if (VecType && VecType->getNumElements() == 1 &&
8121 isLaxVectorConversion(RHSType, LHSType)) {
8122 ExprResult *VecExpr = &RHS;
8123 *VecExpr = ImpCastExprToType(VecExpr->get(), LHSType, CK_BitCast);
8124 Kind = CK_BitCast;
8125 return Compatible;
8126 }
8127 }
8128
8129 return Incompatible;
8130 }
8131
8132 // Diagnose attempts to convert between __float128 and long double where
8133 // such conversions currently can't be handled.
8134 if (unsupportedTypeConversion(*this, LHSType, RHSType))
8135 return Incompatible;
8136
8137 // Disallow assigning a _Complex to a real type in C++ mode since it simply
8138 // discards the imaginary part.
8139 if (getLangOpts().CPlusPlus && RHSType->getAs<ComplexType>() &&
8140 !LHSType->getAs<ComplexType>())
8141 return Incompatible;
8142
8143 // Arithmetic conversions.
8144 if (LHSType->isArithmeticType() && RHSType->isArithmeticType() &&
8145 !(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) {
8146 if (ConvertRHS)
8147 Kind = PrepareScalarCast(RHS, LHSType);
8148 return Compatible;
8149 }
8150
8151 // CHERI callbacks may only be cast to other cheri callback types
8152 bool RHSIsCallback = false;
8153 bool LHSIsCallback = false;
8154 if (auto RHSPointer = dyn_cast<PointerType>(RHSType))
8155 if (auto RHSFnPTy = RHSPointer->getPointeeType()->getAs<FunctionType>())
8156 if (RHSFnPTy->getCallConv() == CC_CHERICCallback)
8157 RHSIsCallback = true;
8158 if (auto LHSPointer = dyn_cast<PointerType>(LHSType))
8159 if (auto LHSFnPTy = LHSPointer->getPointeeType()->getAs<FunctionType>())
8160 if (LHSFnPTy->getCallConv() == CC_CHERICCallback)
8161 LHSIsCallback = true;
8162 if (RHSIsCallback != LHSIsCallback)
8163 return Incompatible;
8164
8165 // Conversions to normal pointers.
8166 if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) {
8167 // U* -> T*
8168 if (const PointerType *RHSPointer = dyn_cast<PointerType>(RHSType)) {
8169 LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
8170 LangAS AddrSpaceR = RHSPointer->getPointeeType().getAddressSpace();
8171 if (AddrSpaceL != AddrSpaceR)
8172 Kind = CK_AddressSpaceConversion;
8173 else if (LHSPointer->isFunctionPointerType() && RHSPointer->isFunctionPointerType()) {
8174 // only allow implicit casts to and from function pointer capabilities
8175 if (!LHSPointer->isCHERICapability() && RHSPointer->isCHERICapability())
8176 Kind = CK_CHERICapabilityToPointer;
8177 else if (LHSPointer->isCHERICapability() && !RHSPointer->isCHERICapability())
8178 Kind = CK_PointerToCHERICapability;
8179 else
8180 Kind = CK_BitCast;
8181 } else if (LHSPointer->isCHERICapability() != RHSPointer->isCHERICapability()) {
8182 // all other implicit casts to and from capabilities are not allowed
8183 Kind = RHSPointer->isCHERICapability() ? CK_CHERICapabilityToPointer :
8184 CK_PointerToCHERICapability;
8185 return RHSPointer->isCHERICapability() ? CHERICapabilityToPointer :
8186 PointerToCHERICapability;
8187 } else {
8188 if (Context.hasCvrSimilarType(RHSType, LHSType))
8189 Kind = CK_NoOp;
8190 else
8191 Kind = CK_BitCast;
8192 if (RHSPointer->isCHERICapability() && isa<PointerType>(OrigRHSType) &&
8193 RHSPointer->getPointeeType()->isVoidType())
8194 if (auto *TT = dyn_cast<TypedefType>(
8195 cast<PointerType>(OrigRHSType)->getPointeeType())) {
8196 unsigned FromAlign = Context.getTypeAlignInChars(TT).getQuantity();
8197 unsigned ToAlign =
8198 Context.getTypeAlignInChars(LHSType).getQuantity();
8199 if ((FromAlign > 1) && (ToAlign > FromAlign))
8200 Diag(RHS.get()->getExprLoc(), diag::err_cheri_ptr_align) <<
8201 OrigRHSType << LHSType << FromAlign << ToAlign;
8202 }
8203 }
8204 return checkPointerTypesForAssignment(*this, LHSType, RHSType);
8205 }
8206
8207 // int -> T*
8208 if (RHSType->isIntegerType()) {
8209 // Implicit casts from int -> memory capabilities are not allowed (except for null)
8210 const Expr::NullPointerConstantKind RHSNullKind =
8211 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
8212 bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
8213 if (LHSPointer->isCHERICapability() && !RHSIsNull &&
8214 !RHSType->isIntCapType())
8215 return Incompatible;
8216 Kind = CK_IntegralToPointer; // FIXME: null?
8217 return IntToPointer;
8218 }
8219
8220 // C pointers are not compatible with ObjC object pointers,
8221 // with two exceptions:
8222 if (isa<ObjCObjectPointerType>(RHSType)) {
8223 // - conversions to void*
8224 if (LHSPointer->getPointeeType()->isVoidType()) {
8225 Kind = CK_BitCast;
8226 return Compatible;
8227 }
8228
8229 // - conversions from 'Class' to the redefinition type
8230 if (RHSType->isObjCClassType() &&
8231 Context.hasSameType(LHSType,
8232 Context.getObjCClassRedefinitionType())) {
8233 Kind = CK_BitCast;
8234 return Compatible;
8235 }
8236
8237 Kind = CK_BitCast;
8238 return IncompatiblePointer;
8239 }
8240
8241 // U^ -> void*
8242 if (RHSType->getAs<BlockPointerType>()) {
8243 if (LHSPointer->getPointeeType()->isVoidType()) {
8244 LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
8245 LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
8246 ->getPointeeType()
8247 .getAddressSpace();
8248 Kind =
8249 AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
8250 return Compatible;
8251 }
8252 }
8253
8254 return Incompatible;
8255 }
8256
8257 // Conversions to block pointers.
8258 if (isa<BlockPointerType>(LHSType)) {
8259 // U^ -> T^
8260 if (RHSType->isBlockPointerType()) {
8261 LangAS AddrSpaceL = LHSType->getAs<BlockPointerType>()
8262 ->getPointeeType()
8263 .getAddressSpace();
8264 LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
8265 ->getPointeeType()
8266 .getAddressSpace();
8267 Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
8268 return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType);
8269 }
8270
8271 // int or null -> T^
8272 if (RHSType->isIntegerType()) {
8273 Kind = CK_IntegralToPointer; // FIXME: null
8274 return IntToBlockPointer;
8275 }
8276
8277 // id -> T^
8278 if (getLangOpts().ObjC && RHSType->isObjCIdType()) {
8279 Kind = CK_AnyPointerToBlockPointerCast;
8280 return Compatible;
8281 }
8282
8283 // void* -> T^
8284 if (const PointerType *RHSPT = RHSType->getAs<PointerType>())
8285 if (RHSPT->getPointeeType()->isVoidType()) {
8286 Kind = CK_AnyPointerToBlockPointerCast;
8287 return Compatible;
8288 }
8289
8290 return Incompatible;
8291 }
8292
8293 // Conversions to Objective-C pointers.
8294 if (isa<ObjCObjectPointerType>(LHSType)) {
8295 // A* -> B*
8296 if (RHSType->isObjCObjectPointerType()) {
8297 Kind = CK_BitCast;
8298 Sema::AssignConvertType result =
8299 checkObjCPointerTypesForAssignment(*this, LHSType, RHSType);
8300 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
8301 result == Compatible &&
8302 !CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType))
8303 result = IncompatibleObjCWeakRef;
8304 return result;
8305 }
8306
8307 // int or null -> A*
8308 if (RHSType->isIntegerType()) {
8309 Kind = CK_IntegralToPointer; // FIXME: null
8310 return IntToPointer;
8311 }
8312
8313 // In general, C pointers are not compatible with ObjC object pointers,
8314 // with two exceptions:
8315 if (isa<PointerType>(RHSType)) {
8316 Kind = CK_CPointerToObjCPointerCast;
8317
8318 // - conversions from 'void*'
8319 if (RHSType->isVoidPointerType()) {
8320 return Compatible;
8321 }
8322
8323 // - conversions to 'Class' from its redefinition type
8324 if (LHSType->isObjCClassType() &&
8325 Context.hasSameType(RHSType,
8326 Context.getObjCClassRedefinitionType())) {
8327 return Compatible;
8328 }
8329
8330 return IncompatiblePointer;
8331 }
8332
8333 // Only under strict condition T^ is compatible with an Objective-C pointer.
8334 if (RHSType->isBlockPointerType() &&
8335 LHSType->isBlockCompatibleObjCPointerType(Context)) {
8336 if (ConvertRHS)
8337 maybeExtendBlockObject(RHS);
8338 Kind = CK_BlockPointerToObjCPointerCast;
8339 return Compatible;
8340 }
8341
8342 return Incompatible;
8343 }
8344
8345 // Conversions from pointers that are not covered by the above.
8346 if (const PointerType *RHSPointer = dyn_cast<PointerType>(RHSType)) {
8347 // T* -> _Bool
8348 if (LHSType == Context.BoolTy) {
8349 Kind = CK_PointerToBoolean;
8350 return Compatible;
8351 }
8352
8353 // T* -> int
8354 if (LHSType->isIntegerType()) {
8355 // Implicit casts from memory capabilities -> int are not allowed (except for null)
8356 const Expr::NullPointerConstantKind RHSNullKind =
8357 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
8358 bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
8359 if (RHSPointer->isCHERICapability() && !RHSIsNull &&
8360 !LHSType->isIntCapType())
8361 return Incompatible;
8362 Kind = CK_PointerToIntegral;
8363 return PointerToInt;
8364 }
8365
8366 return Incompatible;
8367 }
8368
8369 // Conversions from Objective-C pointers that are not covered by the above.
8370 if (isa<ObjCObjectPointerType>(RHSType)) {
8371 // T* -> _Bool
8372 if (LHSType == Context.BoolTy) {
8373 Kind = CK_PointerToBoolean;
8374 return Compatible;
8375 }
8376
8377 // T* -> int
8378 if (LHSType->isIntegerType()) {
8379 Kind = CK_PointerToIntegral;
8380 return PointerToInt;
8381 }
8382
8383 return Incompatible;
8384 }
8385
8386 // struct A -> struct B
8387 if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) {
8388 if (Context.typesAreCompatible(LHSType, RHSType)) {
8389 Kind = CK_NoOp;
8390 return Compatible;
8391 }
8392 }
8393
8394 if (LHSType->isSamplerT() && RHSType->isIntegerType()) {
8395 Kind = CK_IntToOCLSampler;
8396 return Compatible;
8397 }
8398
8399 return Incompatible;
8400}
8401
8402/// Constructs a transparent union from an expression that is
8403/// used to initialize the transparent union.
8404static void ConstructTransparentUnion(Sema &S, ASTContext &C,
8405 ExprResult &EResult, QualType UnionType,
8406 FieldDecl *Field) {
8407 // Build an initializer list that designates the appropriate member
8408 // of the transparent union.
8409 Expr *E = EResult.get();
8410 InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(),
8411 E, SourceLocation());
8412 Initializer->setType(UnionType);
8413 Initializer->setInitializedFieldInUnion(Field);
8414
8415 // Build a compound literal constructing a value of the transparent
8416 // union type from this initializer list.
8417 TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType);
8418 EResult = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType,
8419 VK_RValue, Initializer, false);
8420}
8421
8422Sema::AssignConvertType
8423Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType,
8424 ExprResult &RHS) {
8425 QualType RHSType = RHS.get()->getType();
8426
8427 // If the ArgType is a Union type, we want to handle a potential
8428 // transparent_union GCC extension.
8429 const RecordType *UT = ArgType->getAsUnionType();
8430 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
8431 return Incompatible;
8432
8433 // The field to initialize within the transparent union.
8434 RecordDecl *UD = UT->getDecl();
8435 FieldDecl *InitField = nullptr;
8436 // It's compatible if the expression matches any of the fields.
8437 for (auto *it : UD->fields()) {
8438 if (it->getType()->isPointerType()) {
8439 // If the transparent union contains a pointer type, we allow:
8440 // 1) void pointer
8441 // 2) null pointer constant
8442 if (RHSType->isPointerType())
8443 if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
8444 RHS = ImpCastExprToType(RHS.get(), it->getType(), CK_BitCast);
8445 InitField = it;
8446 break;
8447 }
8448
8449 if (RHS.get()->isNullPointerConstant(Context,
8450 Expr::NPC_ValueDependentIsNull)) {
8451 RHS = ImpCastExprToType(RHS.get(), it->getType(),
8452 CK_NullToPointer);
8453 InitField = it;
8454 break;
8455 }
8456 }
8457
8458 CastKind Kind;
8459 if (CheckAssignmentConstraints(it->getType(), RHS, Kind)
8460 == Compatible) {
8461 RHS = ImpCastExprToType(RHS.get(), it->getType(), Kind);
8462 InitField = it;
8463 break;
8464 }
8465 }
8466
8467 if (!InitField)
8468 return Incompatible;
8469
8470 ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField);
8471 return Compatible;
8472}
8473
8474Sema::AssignConvertType
8475Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &CallerRHS,
8476 bool Diagnose,
8477 bool DiagnoseCFAudited,
8478 bool ConvertRHS) {
8479 // We need to be able to tell the caller whether we diagnosed a problem, if
8480 // they ask us to issue diagnostics.
8481 assert((ConvertRHS || !Diagnose) && "can't indicate whether we diagnosed");
8482
8483 // If ConvertRHS is false, we want to leave the caller's RHS untouched. Sadly,
8484 // we can't avoid *all* modifications at the moment, so we need some somewhere
8485 // to put the updated value.
8486 ExprResult LocalRHS = CallerRHS;
8487 ExprResult &RHS = ConvertRHS ? CallerRHS : LocalRHS;
8488
8489 if (const auto *LHSPtrType = LHSType->getAs<PointerType>()) {
8490 if (const auto *RHSPtrType = RHS.get()->getType()->getAs<PointerType>()) {
8491 if (RHSPtrType->getPointeeType()->hasAttr(attr::NoDeref) &&
8492 !LHSPtrType->getPointeeType()->hasAttr(attr::NoDeref)) {
8493 Diag(RHS.get()->getExprLoc(),
8494 diag::warn_noderef_to_dereferenceable_pointer)
8495 << RHS.get()->getSourceRange();
8496 }
8497 }
8498 }
8499
8500 if (getLangOpts().CPlusPlus) {
8501 if (!LHSType->isRecordType() && !LHSType->isAtomicType()) {
8502 // C++ 5.17p3: If the left operand is not of class type, the
8503 // expression is implicitly converted (C++ 4) to the
8504 // cv-unqualified type of the left operand.
8505 QualType RHSType = RHS.get()->getType();
8506 if (Diagnose) {
8507 RHS = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
8508 AA_Assigning);
8509 } else {
8510 ImplicitConversionSequence ICS =
8511 TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
8512 /*SuppressUserConversions=*/false,
8513 /*AllowExplicit=*/false,
8514 /*InOverloadResolution=*/false,
8515 /*CStyle=*/false,
8516 /*AllowObjCWritebackConversion=*/false);
8517 if (ICS.isFailure())
8518 return Incompatible;
8519 RHS = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
8520 ICS, AA_Assigning);
8521 }
8522 if (RHS.isInvalid())
8523 return Incompatible;
8524 Sema::AssignConvertType result = Compatible;
8525 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
8526 !CheckObjCARCUnavailableWeakConversion(LHSType, RHSType))
8527 result = IncompatibleObjCWeakRef;
8528 return result;
8529 }
8530
8531 // FIXME: Currently, we fall through and treat C++ classes like C
8532 // structures.
8533 // FIXME: We also fall through for atomics; not sure what should
8534 // happen there, though.
8535 } else if (RHS.get()->getType() == Context.OverloadTy) {
8536 // As a set of extensions to C, we support overloading on functions. These
8537 // functions need to be resolved here.
8538 DeclAccessPair DAP;
8539 if (FunctionDecl *FD = ResolveAddressOfOverloadedFunction(
8540 RHS.get(), LHSType, /*Complain=*/false, DAP))
8541 RHS = FixOverloadedFunctionReference(RHS.get(), DAP, FD);
8542 else
8543 return Incompatible;
8544 }
8545
8546 // C99 6.5.16.1p1: the left operand is a pointer and the right is
8547 // a null pointer constant.
8548 if ((LHSType->isPointerType() || LHSType->isObjCObjectPointerType() ||
8549 LHSType->isBlockPointerType()) &&
8550 RHS.get()->isNullPointerConstant(Context,
8551 Expr::NPC_ValueDependentIsNull)) {
8552 if (Diagnose || ConvertRHS) {
8553 CastKind Kind;
8554 CXXCastPath Path;
8555 CheckPointerConversion(RHS.get(), LHSType, Kind, Path,
8556 /*IgnoreBaseAccess=*/false, Diagnose);
8557 if (ConvertRHS)
8558 RHS = ImpCastExprToType(RHS.get(), LHSType, Kind, VK_RValue, &Path);
8559 }
8560 return Compatible;
8561 }
8562
8563 // OpenCL queue_t type assignment.
8564 if (LHSType->isQueueT() && RHS.get()->isNullPointerConstant(
8565 Context, Expr::NPC_ValueDependentIsNull)) {
8566 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
8567 return Compatible;
8568 }
8569
8570 // This check seems unnatural, however it is necessary to ensure the proper
8571 // conversion of functions/arrays. If the conversion were done for all
8572 // DeclExpr's (created by ActOnIdExpression), it would mess up the unary
8573 // expressions that suppress this implicit conversion (&, sizeof).
8574 //
8575 // Suppress this for references: C++ 8.5.3p5.
8576 if (!LHSType->isReferenceType()) {
8577 // FIXME: We potentially allocate here even if ConvertRHS is false.
8578 RHS = DefaultFunctionArrayLvalueConversion(RHS.get(), Diagnose);
8579 if (RHS.isInvalid())
8580 return Incompatible;
8581 }
8582 CastKind Kind;
8583 Sema::AssignConvertType result =
8584 CheckAssignmentConstraints(LHSType, RHS, Kind, ConvertRHS);
8585
8586 // C99 6.5.16.1p2: The value of the right operand is converted to the
8587 // type of the assignment expression.
8588 // CheckAssignmentConstraints allows the left-hand side to be a reference,
8589 // so that we can use references in built-in functions even in C.
8590 // The getNonReferenceType() call makes sure that the resulting expression
8591 // does not have reference type.
8592 if (result != Incompatible && RHS.get()->getType() != LHSType) {
8593 QualType Ty = LHSType.getNonLValueExprType(Context);
8594 Expr *E = RHS.get();
8595
8596 // Check for various Objective-C errors. If we are not reporting
8597 // diagnostics and just checking for errors, e.g., during overload
8598 // resolution, return Incompatible to indicate the failure.
8599 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
8600 CheckObjCConversion(SourceRange(), Ty, E, CCK_ImplicitConversion,
8601 Diagnose, DiagnoseCFAudited) != ACR_okay) {
8602 if (!Diagnose)
8603 return Incompatible;
8604 }
8605 if (getLangOpts().ObjC &&
8606 (CheckObjCBridgeRelatedConversions(E->getBeginLoc(), LHSType,
8607 E->getType(), E, Diagnose) ||
8608 ConversionToObjCStringLiteralCheck(LHSType, E, Diagnose))) {
8609 if (!Diagnose)
8610 return Incompatible;
8611 // Replace the expression with a corrected version and continue so we
8612 // can find further errors.
8613 RHS = E;
8614 return Compatible;
8615 }
8616
8617 if (ConvertRHS)
8618 RHS = ImpCastExprToType(E, Ty, Kind);
8619 }
8620
8621 return result;
8622}
8623
8624namespace {
8625/// The original operand to an operator, prior to the application of the usual
8626/// arithmetic conversions and converting the arguments of a builtin operator
8627/// candidate.
8628struct OriginalOperand {
8629 explicit OriginalOperand(Expr *Op) : Orig(Op), Conversion(nullptr) {
8630 if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Op))
8631 Op = MTE->GetTemporaryExpr();
8632 if (auto *BTE = dyn_cast<CXXBindTemporaryExpr>(Op))
8633 Op = BTE->getSubExpr();
8634 if (auto *ICE = dyn_cast<ImplicitCastExpr>(Op)) {
8635 Orig = ICE->getSubExprAsWritten();
8636 Conversion = ICE->getConversionFunction();
8637 }
8638 }
8639
8640 QualType getType() const { return Orig->getType(); }
8641
8642 Expr *Orig;
8643 NamedDecl *Conversion;
8644};
8645}
8646
8647QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS,
8648 ExprResult &RHS) {
8649 OriginalOperand OrigLHS(LHS.get()), OrigRHS(RHS.get());
8650
8651 Diag(Loc, diag::err_typecheck_invalid_operands)
8652 << OrigLHS.getType() << OrigRHS.getType()
8653 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
8654
8655 // If a user-defined conversion was applied to either of the operands prior
8656 // to applying the built-in operator rules, tell the user about it.
8657 if (OrigLHS.Conversion) {
8658 Diag(OrigLHS.Conversion->getLocation(),
8659 diag::note_typecheck_invalid_operands_converted)
8660 << 0 << LHS.get()->getType();
8661 }
8662 if (OrigRHS.Conversion) {
8663 Diag(OrigRHS.Conversion->getLocation(),
8664 diag::note_typecheck_invalid_operands_converted)
8665 << 1 << RHS.get()->getType();
8666 }
8667
8668 return QualType();
8669}
8670
8671// Diagnose cases where a scalar was implicitly converted to a vector and
8672// diagnose the underlying types. Otherwise, diagnose the error
8673// as invalid vector logical operands for non-C++ cases.
8674QualType Sema::InvalidLogicalVectorOperands(SourceLocation Loc, ExprResult &LHS,
8675 ExprResult &RHS) {
8676 QualType LHSType = LHS.get()->IgnoreImpCasts()->getType();
8677 QualType RHSType = RHS.get()->IgnoreImpCasts()->getType();
8678
8679 bool LHSNatVec = LHSType->isVectorType();
8680 bool RHSNatVec = RHSType->isVectorType();
8681
8682 if (!(LHSNatVec && RHSNatVec)) {
8683 Expr *Vector = LHSNatVec ? LHS.get() : RHS.get();
8684 Expr *NonVector = !LHSNatVec ? LHS.get() : RHS.get();
8685 Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
8686 << 0 << Vector->getType() << NonVector->IgnoreImpCasts()->getType()
8687 << Vector->getSourceRange();
8688 return QualType();
8689 }
8690
8691 Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
8692 << 1 << LHSType << RHSType << LHS.get()->getSourceRange()
8693 << RHS.get()->getSourceRange();
8694
8695 return QualType();
8696}
8697
8698/// Try to convert a value of non-vector type to a vector type by converting
8699/// the type to the element type of the vector and then performing a splat.
8700/// If the language is OpenCL, we only use conversions that promote scalar
8701/// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
8702/// for float->int.
8703///
8704/// OpenCL V2.0 6.2.6.p2:
8705/// An error shall occur if any scalar operand type has greater rank
8706/// than the type of the vector element.
8707///
8708/// \param scalar - if non-null, actually perform the conversions
8709/// \return true if the operation fails (but without diagnosing the failure)
8710static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
8711 QualType scalarTy,
8712 QualType vectorEltTy,
8713 QualType vectorTy,
8714 unsigned &DiagID) {
8715 // The conversion to apply to the scalar before splatting it,
8716 // if necessary.
8717 CastKind scalarCast = CK_NoOp;
8718
8719 if (vectorEltTy->isIntegralType(S.Context)) {
8720 if (S.getLangOpts().OpenCL && (scalarTy->isRealFloatingType() ||
8721 (scalarTy->isIntegerType() &&
8722 S.Context.getIntegerTypeOrder(vectorEltTy, scalarTy) < 0))) {
8723 DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
8724 return true;
8725 }
8726 if (!scalarTy->isIntegralType(S.Context))
8727 return true;
8728 scalarCast = CK_IntegralCast;
8729 } else if (vectorEltTy->isRealFloatingType()) {
8730 if (scalarTy->isRealFloatingType()) {
8731 if (S.getLangOpts().OpenCL &&
8732 S.Context.getFloatingTypeOrder(vectorEltTy, scalarTy) < 0) {
8733 DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
8734 return true;
8735 }
8736 scalarCast = CK_FloatingCast;
8737 }
8738 else if (scalarTy->isIntegralType(S.Context))
8739 scalarCast = CK_IntegralToFloating;
8740 else
8741 return true;
8742 } else {
8743 return true;
8744 }
8745
8746 // Adjust scalar if desired.
8747 if (scalar) {
8748 if (scalarCast != CK_NoOp)
8749 *scalar = S.ImpCastExprToType(scalar->get(), vectorEltTy, scalarCast);
8750 *scalar = S.ImpCastExprToType(scalar->get(), vectorTy, CK_VectorSplat);
8751 }
8752 return false;
8753}
8754
8755/// Convert vector E to a vector with the same number of elements but different
8756/// element type.
8757static ExprResult convertVector(Expr *E, QualType ElementType, Sema &S) {
8758 const auto *VecTy = E->getType()->getAs<VectorType>();
8759 assert(VecTy && "Expression E must be a vector");
8760 QualType NewVecTy = S.Context.getVectorType(ElementType,
8761 VecTy->getNumElements(),
8762 VecTy->getVectorKind());
8763
8764 // Look through the implicit cast. Return the subexpression if its type is
8765 // NewVecTy.
8766 if (auto *ICE = dyn_cast<ImplicitCastExpr>(E))
8767 if (ICE->getSubExpr()->getType() == NewVecTy)
8768 return ICE->getSubExpr();
8769
8770 auto Cast = ElementType->isIntegerType() ? CK_IntegralCast : CK_FloatingCast;
8771 return S.ImpCastExprToType(E, NewVecTy, Cast);
8772}
8773
8774/// Test if a (constant) integer Int can be casted to another integer type
8775/// IntTy without losing precision.
8776static bool canConvertIntToOtherIntTy(Sema &S, ExprResult *Int,
8777 QualType OtherIntTy) {
8778 QualType IntTy = Int->get()->getType().getUnqualifiedType();
8779
8780 // Reject cases where the value of the Int is unknown as that would
8781 // possibly cause truncation, but accept cases where the scalar can be
8782 // demoted without loss of precision.
8783 Expr::EvalResult EVResult;
8784 bool CstInt = Int->get()->EvaluateAsInt(EVResult, S.Context);
8785 int Order = S.Context.getIntegerTypeOrder(OtherIntTy, IntTy);
8786 bool IntSigned = IntTy->hasSignedIntegerRepresentation();
8787 bool OtherIntSigned = OtherIntTy->hasSignedIntegerRepresentation();
8788
8789 if (CstInt) {
8790 // If the scalar is constant and is of a higher order and has more active
8791 // bits that the vector element type, reject it.
8792 llvm::APSInt Result = EVResult.Val.getInt();
8793 unsigned NumBits = IntSigned
8794 ? (Result.isNegative() ? Result.getMinSignedBits()
8795 : Result.getActiveBits())
8796 : Result.getActiveBits();
8797 if (Order < 0 && S.Context.getIntWidth(OtherIntTy) < NumBits)
8798 return true;
8799
8800 // If the signedness of the scalar type and the vector element type
8801 // differs and the number of bits is greater than that of the vector
8802 // element reject it.
8803 return (IntSigned != OtherIntSigned &&
8804 NumBits > S.Context.getIntWidth(OtherIntTy));
8805 }
8806
8807 // Reject cases where the value of the scalar is not constant and it's
8808 // order is greater than that of the vector element type.
8809 return (Order < 0);
8810}
8811
8812/// Test if a (constant) integer Int can be casted to floating point type
8813/// FloatTy without losing precision.
8814static bool canConvertIntTyToFloatTy(Sema &S, ExprResult *Int,
8815 QualType FloatTy) {
8816 QualType IntTy = Int->get()->getType().getUnqualifiedType();
8817
8818 // Determine if the integer constant can be expressed as a floating point
8819 // number of the appropriate type.
8820 Expr::EvalResult EVResult;
8821 bool CstInt = Int->get()->EvaluateAsInt(EVResult, S.Context);
8822
8823 uint64_t Bits = 0;
8824 if (CstInt) {
8825 // Reject constants that would be truncated if they were converted to
8826 // the floating point type. Test by simple to/from conversion.
8827 // FIXME: Ideally the conversion to an APFloat and from an APFloat
8828 // could be avoided if there was a convertFromAPInt method
8829 // which could signal back if implicit truncation occurred.
8830 llvm::APSInt Result = EVResult.Val.getInt();
8831 llvm::APFloat Float(S.Context.getFloatTypeSemantics(FloatTy));
8832 Float.convertFromAPInt(Result, IntTy->hasSignedIntegerRepresentation(),
8833 llvm::APFloat::rmTowardZero);
8834 llvm::APSInt ConvertBack(S.Context.getIntWidth(IntTy),
8835 !IntTy->hasSignedIntegerRepresentation());
8836 bool Ignored = false;
8837 Float.convertToInteger(ConvertBack, llvm::APFloat::rmNearestTiesToEven,
8838 &Ignored);
8839 if (Result != ConvertBack)
8840 return true;
8841 } else {
8842 // Reject types that cannot be fully encoded into the mantissa of
8843 // the float.
8844 Bits = S.Context.getTypeSize(IntTy);
8845 unsigned FloatPrec = llvm::APFloat::semanticsPrecision(
8846 S.Context.getFloatTypeSemantics(FloatTy));
8847 if (Bits > FloatPrec)
8848 return true;
8849 }
8850
8851 return false;
8852}
8853
8854/// Attempt to convert and splat Scalar into a vector whose types matches
8855/// Vector following GCC conversion rules. The rule is that implicit
8856/// conversion can occur when Scalar can be casted to match Vector's element
8857/// type without causing truncation of Scalar.
8858static bool tryGCCVectorConvertAndSplat(Sema &S, ExprResult *Scalar,
8859 ExprResult *Vector) {
8860 QualType ScalarTy = Scalar->get()->getType().getUnqualifiedType();
8861 QualType VectorTy = Vector->get()->getType().getUnqualifiedType();
8862 const VectorType *VT = VectorTy->getAs<VectorType>();
8863
8864 assert(!isa<ExtVectorType>(VT) &&
8865 "ExtVectorTypes should not be handled here!");
8866
8867 QualType VectorEltTy = VT->getElementType();
8868
8869 // Reject cases where the vector element type or the scalar element type are
8870 // not integral or floating point types.
8871 if (!VectorEltTy->isArithmeticType() || !ScalarTy->isArithmeticType())
8872 return true;
8873
8874 // The conversion to apply to the scalar before splatting it,
8875 // if necessary.
8876 CastKind ScalarCast = CK_NoOp;
8877
8878 // Accept cases where the vector elements are integers and the scalar is
8879 // an integer.
8880 // FIXME: Notionally if the scalar was a floating point value with a precise
8881 // integral representation, we could cast it to an appropriate integer
8882 // type and then perform the rest of the checks here. GCC will perform
8883 // this conversion in some cases as determined by the input language.
8884 // We should accept it on a language independent basis.
8885 if (VectorEltTy->isIntegralType(S.Context) &&
8886 ScalarTy->isIntegralType(S.Context) &&
8887 S.Context.getIntegerTypeOrder(VectorEltTy, ScalarTy)) {
8888
8889 if (canConvertIntToOtherIntTy(S, Scalar, VectorEltTy))
8890 return true;
8891
8892 ScalarCast = CK_IntegralCast;
8893 } else if (VectorEltTy->isRealFloatingType()) {
8894 if (ScalarTy->isRealFloatingType()) {
8895
8896 // Reject cases where the scalar type is not a constant and has a higher
8897 // Order than the vector element type.
8898 llvm::APFloat Result(0.0);
8899 bool CstScalar = Scalar->get()->EvaluateAsFloat(Result, S.Context);
8900 int Order = S.Context.getFloatingTypeOrder(VectorEltTy, ScalarTy);
8901 if (!CstScalar && Order < 0)
8902 return true;
8903
8904 // If the scalar cannot be safely casted to the vector element type,
8905 // reject it.
8906 if (CstScalar) {
8907 bool Truncated = false;
8908 Result.convert(S.Context.getFloatTypeSemantics(VectorEltTy),
8909 llvm::APFloat::rmNearestTiesToEven, &Truncated);
8910 if (Truncated)
8911 return true;
8912 }
8913
8914 ScalarCast = CK_FloatingCast;
8915 } else if (ScalarTy->isIntegralType(S.Context)) {
8916 if (canConvertIntTyToFloatTy(S, Scalar, VectorEltTy))
8917 return true;
8918
8919 ScalarCast = CK_IntegralToFloating;
8920 } else
8921 return true;
8922 }
8923
8924 // Adjust scalar if desired.
8925 if (Scalar) {
8926 if (ScalarCast != CK_NoOp)
8927 *Scalar = S.ImpCastExprToType(Scalar->get(), VectorEltTy, ScalarCast);
8928 *Scalar = S.ImpCastExprToType(Scalar->get(), VectorTy, CK_VectorSplat);
8929 }
8930 return false;
8931}
8932
8933QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
8934 SourceLocation Loc, bool IsCompAssign,
8935 bool AllowBothBool,
8936 bool AllowBoolConversions) {
8937 if (!IsCompAssign) {
8938 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
8939 if (LHS.isInvalid())
8940 return QualType();
8941 }
8942 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
8943 if (RHS.isInvalid())
8944 return QualType();
8945
8946 // For conversion purposes, we ignore any qualifiers.
8947 // For example, "const float" and "float" are equivalent.
8948 QualType LHSType = LHS.get()->getType().getUnqualifiedType();
8949 QualType RHSType = RHS.get()->getType().getUnqualifiedType();
8950
8951 const VectorType *LHSVecType = LHSType->getAs<VectorType>();
8952 const VectorType *RHSVecType = RHSType->getAs<VectorType>();
8953 assert(LHSVecType || RHSVecType);
8954
8955 // AltiVec-style "vector bool op vector bool" combinations are allowed
8956 // for some operators but not others.
8957 if (!AllowBothBool &&
8958 LHSVecType && LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
8959 RHSVecType && RHSVecType->getVectorKind() == VectorType::AltiVecBool)
8960 return InvalidOperands(Loc, LHS, RHS);
8961
8962 // If the vector types are identical, return.
8963 if (Context.hasSameType(LHSType, RHSType))
8964 return LHSType;
8965
8966 // If we have compatible AltiVec and GCC vector types, use the AltiVec type.
8967 if (LHSVecType && RHSVecType &&
8968 Context.areCompatibleVectorTypes(LHSType, RHSType)) {
8969 if (isa<ExtVectorType>(LHSVecType)) {
8970 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
8971 return LHSType;
8972 }
8973
8974 if (!IsCompAssign)
8975 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
8976 return RHSType;
8977 }
8978
8979 // AllowBoolConversions says that bool and non-bool AltiVec vectors
8980 // can be mixed, with the result being the non-bool type. The non-bool
8981 // operand must have integer element type.
8982 if (AllowBoolConversions && LHSVecType && RHSVecType &&
8983 LHSVecType->getNumElements() == RHSVecType->getNumElements() &&
8984 (Context.getTypeSize(LHSVecType->getElementType()) ==
8985 Context.getTypeSize(RHSVecType->getElementType()))) {
8986 if (LHSVecType->getVectorKind() == VectorType::AltiVecVector &&
8987 LHSVecType->getElementType()->isIntegerType() &&
8988 RHSVecType->getVectorKind() == VectorType::AltiVecBool) {
8989 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
8990 return LHSType;
8991 }
8992 if (!IsCompAssign &&
8993 LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
8994 RHSVecType->getVectorKind() == VectorType::AltiVecVector &&
8995 RHSVecType->getElementType()->isIntegerType()) {
8996 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
8997 return RHSType;
8998 }
8999 }
9000
9001 // If there's a vector type and a scalar, try to convert the scalar to
9002 // the vector element type and splat.
9003 unsigned DiagID = diag::err_typecheck_vector_not_convertable;
9004 if (!RHSVecType) {
9005 if (isa<ExtVectorType>(LHSVecType)) {
9006 if (!tryVectorConvertAndSplat(*this, &RHS, RHSType,
9007 LHSVecType->getElementType(), LHSType,
9008 DiagID))
9009 return LHSType;
9010 } else {
9011 if (!tryGCCVectorConvertAndSplat(*this, &RHS, &LHS))
9012 return LHSType;
9013 }
9014 }
9015 if (!LHSVecType) {
9016 if (isa<ExtVectorType>(RHSVecType)) {
9017 if (!tryVectorConvertAndSplat(*this, (IsCompAssign ? nullptr : &LHS),
9018 LHSType, RHSVecType->getElementType(),
9019 RHSType, DiagID))
9020 return RHSType;
9021 } else {
9022 if (LHS.get()->getValueKind() == VK_LValue ||
9023 !tryGCCVectorConvertAndSplat(*this, &LHS, &RHS))
9024 return RHSType;
9025 }
9026 }
9027
9028 // FIXME: The code below also handles conversion between vectors and
9029 // non-scalars, we should break this down into fine grained specific checks
9030 // and emit proper diagnostics.
9031 QualType VecType = LHSVecType ? LHSType : RHSType;
9032 const VectorType *VT = LHSVecType ? LHSVecType : RHSVecType;
9033 QualType OtherType = LHSVecType ? RHSType : LHSType;
9034 ExprResult *OtherExpr = LHSVecType ? &RHS : &LHS;
9035 if (isLaxVectorConversion(OtherType, VecType)) {
9036 // If we're allowing lax vector conversions, only the total (data) size
9037 // needs to be the same. For non compound assignment, if one of the types is
9038 // scalar, the result is always the vector type.
9039 if (!IsCompAssign) {
9040 *OtherExpr = ImpCastExprToType(OtherExpr->get(), VecType, CK_BitCast);
9041 return VecType;
9042 // In a compound assignment, lhs += rhs, 'lhs' is a lvalue src, forbidding
9043 // any implicit cast. Here, the 'rhs' should be implicit casted to 'lhs'
9044 // type. Note that this is already done by non-compound assignments in
9045 // CheckAssignmentConstraints. If it's a scalar type, only bitcast for
9046 // <1 x T> -> T. The result is also a vector type.
9047 } else if (OtherType->isExtVectorType() || OtherType->isVectorType() ||
9048 (OtherType->isScalarType() && VT->getNumElements() == 1)) {
9049 ExprResult *RHSExpr = &RHS;
9050 *RHSExpr = ImpCastExprToType(RHSExpr->get(), LHSType, CK_BitCast);
9051 return VecType;
9052 }
9053 }
9054
9055 // Okay, the expression is invalid.
9056
9057 // If there's a non-vector, non-real operand, diagnose that.
9058 if ((!RHSVecType && !RHSType->isRealType()) ||
9059 (!LHSVecType && !LHSType->isRealType())) {
9060 Diag(Loc, diag::err_typecheck_vector_not_convertable_non_scalar)
9061 << LHSType << RHSType
9062 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9063 return QualType();
9064 }
9065
9066 // OpenCL V1.1 6.2.6.p1:
9067 // If the operands are of more than one vector type, then an error shall
9068 // occur. Implicit conversions between vector types are not permitted, per
9069 // section 6.2.1.
9070 if (getLangOpts().OpenCL &&
9071 RHSVecType && isa<ExtVectorType>(RHSVecType) &&
9072 LHSVecType && isa<ExtVectorType>(LHSVecType)) {
9073 Diag(Loc, diag::err_opencl_implicit_vector_conversion) << LHSType
9074 << RHSType;
9075 return QualType();
9076 }
9077
9078
9079 // If there is a vector type that is not a ExtVector and a scalar, we reach
9080 // this point if scalar could not be converted to the vector's element type
9081 // without truncation.
9082 if ((RHSVecType && !isa<ExtVectorType>(RHSVecType)) ||
9083 (LHSVecType && !isa<ExtVectorType>(LHSVecType))) {
9084 QualType Scalar = LHSVecType ? RHSType : LHSType;
9085 QualType Vector = LHSVecType ? LHSType : RHSType;
9086 unsigned ScalarOrVector = LHSVecType && RHSVecType ? 1 : 0;
9087 Diag(Loc,
9088 diag::err_typecheck_vector_not_convertable_implict_truncation)
9089 << ScalarOrVector << Scalar << Vector;
9090
9091 return QualType();
9092 }
9093
9094 // Otherwise, use the generic diagnostic.
9095 Diag(Loc, DiagID)
9096 << LHSType << RHSType
9097 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9098 return QualType();
9099}
9100
9101// checkArithmeticNull - Detect when a NULL constant is used improperly in an
9102// expression. These are mainly cases where the null pointer is used as an
9103// integer instead of a pointer.
9104static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS,
9105 SourceLocation Loc, bool IsCompare) {
9106 // The canonical way to check for a GNU null is with isNullPointerConstant,
9107 // but we use a bit of a hack here for speed; this is a relatively
9108 // hot path, and isNullPointerConstant is slow.
9109 bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts());
9110 bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts());
9111
9112 QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType();
9113
9114 // Avoid analyzing cases where the result will either be invalid (and
9115 // diagnosed as such) or entirely valid and not something to warn about.
9116 if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() ||
9117 NonNullType->isMemberPointerType() || NonNullType->isFunctionType())
9118 return;
9119
9120 // Comparison operations would not make sense with a null pointer no matter
9121 // what the other expression is.
9122 if (!IsCompare) {
9123 S.Diag(Loc, diag::warn_null_in_arithmetic_operation)
9124 << (LHSNull ? LHS.get()->getSourceRange() : SourceRange())
9125 << (RHSNull ? RHS.get()->getSourceRange() : SourceRange());
9126 return;
9127 }
9128
9129 // The rest of the operations only make sense with a null pointer
9130 // if the other expression is a pointer.
9131 if (LHSNull == RHSNull || NonNullType->isAnyPointerType() ||
9132 NonNullType->canDecayToPointerType())
9133 return;
9134
9135 S.Diag(Loc, diag::warn_null_in_comparison_operation)
9136 << LHSNull /* LHS is NULL */ << NonNullType
9137 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9138}
9139
9140static void DiagnoseDivisionSizeofPointer(Sema &S, Expr *LHS, Expr *RHS,
9141 SourceLocation Loc) {
9142 const auto *LUE = dyn_cast<UnaryExprOrTypeTraitExpr>(LHS);
9143 const auto *RUE = dyn_cast<UnaryExprOrTypeTraitExpr>(RHS);
9144 if (!LUE || !RUE)
9145 return;
9146 if (LUE->getKind() != UETT_SizeOf || LUE->isArgumentType() ||
9147 RUE->getKind() != UETT_SizeOf)
9148 return;
9149
9150 QualType LHSTy = LUE->getArgumentExpr()->IgnoreParens()->getType();
9151 QualType RHSTy;
9152
9153 if (RUE->isArgumentType())
9154 RHSTy = RUE->getArgumentType();
9155 else
9156 RHSTy = RUE->getArgumentExpr()->IgnoreParens()->getType();
9157
9158 if (!LHSTy->isPointerType() || RHSTy->isPointerType())
9159 return;
9160 if (LHSTy->getPointeeType() != RHSTy)
9161 return;
9162
9163 S.Diag(Loc, diag::warn_division_sizeof_ptr) << LHS << LHS->getSourceRange();
9164}
9165
9166static void DiagnoseBadDivideOrRemainderValues(Sema& S, ExprResult &LHS,
9167 ExprResult &RHS,
9168 SourceLocation Loc, bool IsDiv) {
9169 // Check for division/remainder by zero.
9170 Expr::EvalResult RHSValue;
9171 if (!RHS.get()->isValueDependent() &&
9172 RHS.get()->EvaluateAsInt(RHSValue, S.Context) &&
9173 RHSValue.Val.getInt() == 0)
9174 S.DiagRuntimeBehavior(Loc, RHS.get(),
9175 S.PDiag(diag::warn_remainder_division_by_zero)
9176 << IsDiv << RHS.get()->getSourceRange());
9177}
9178
9179QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS,
9180 SourceLocation Loc,
9181 bool IsCompAssign, bool IsDiv) {
9182 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9183
9184 if (LHS.get()->getType()->isVectorType() ||
9185 RHS.get()->getType()->isVectorType())
9186 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
9187 /*AllowBothBool*/getLangOpts().AltiVec,
9188 /*AllowBoolConversions*/false);
9189
9190 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
9191 if (LHS.isInvalid() || RHS.isInvalid())
9192 return QualType();
9193
9194
9195 if (compType.isNull() || !compType->isArithmeticType())
9196 return InvalidOperands(Loc, LHS, RHS);
9197 if (IsDiv) {
9198 DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, IsDiv);
9199 DiagnoseDivisionSizeofPointer(*this, LHS.get(), RHS.get(), Loc);
9200 }
9201 return compType;
9202}
9203
9204QualType Sema::CheckRemainderOperands(
9205 ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
9206 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9207
9208 // Remainder in offset mode will not work for alignment checks since it
9209 // doesn't take the base into account so we warn then
9210 if (getLangOpts().cheriUIntCapUsesOffset() &&
9211 (LHS.get()->getType()->isCHERICapabilityType(Context) ||
9212 RHS.get()->getType()->isCHERICapabilityType(Context)))
9213 DiagRuntimeBehavior(
9214 Loc, RHS.get(),
9215 PDiag(diag::warn_uintcap_bad_bitwise_op)
9216 << 2 /*=modulo*/ << 1 /* used for alignment checks */
9217 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange());
9218
9219 if (LHS.get()->getType()->isVectorType() ||
9220 RHS.get()->getType()->isVectorType()) {
9221 if (LHS.get()->getType()->hasIntegerRepresentation() &&
9222 RHS.get()->getType()->hasIntegerRepresentation())
9223 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
9224 /*AllowBothBool*/getLangOpts().AltiVec,
9225 /*AllowBoolConversions*/false);
9226 return InvalidOperands(Loc, LHS, RHS);
9227 }
9228
9229 QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
9230 if (LHS.isInvalid() || RHS.isInvalid())
9231 return QualType();
9232
9233 if (compType.isNull() || !compType->isIntegerType())
9234 return InvalidOperands(Loc, LHS, RHS);
9235 DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, false /* IsDiv */);
9236 return compType;
9237}
9238
9239/// Diagnose invalid arithmetic on two void pointers.
9240static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc,
9241 Expr *LHSExpr, Expr *RHSExpr) {
9242 S.Diag(Loc, S.getLangOpts().CPlusPlus
9243 ? diag::err_typecheck_pointer_arith_void_type
9244 : diag::ext_gnu_void_ptr)
9245 << 1 /* two pointers */ << LHSExpr->getSourceRange()
9246 << RHSExpr->getSourceRange();
9247}
9248
9249/// Diagnose invalid arithmetic on a void pointer.
9250static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc,
9251 Expr *Pointer) {
9252 S.Diag(Loc, S.getLangOpts().CPlusPlus
9253 ? diag::err_typecheck_pointer_arith_void_type
9254 : diag::ext_gnu_void_ptr)
9255 << 0 /* one pointer */ << Pointer->getSourceRange();
9256}
9257
9258/// Diagnose invalid arithmetic on a null pointer.
9259///
9260/// If \p IsGNUIdiom is true, the operation is using the 'p = (i8*)nullptr + n'
9261/// idiom, which we recognize as a GNU extension.
9262///
9263static void diagnoseArithmeticOnNullPointer(Sema &S, SourceLocation Loc,
9264 Expr *Pointer, bool IsGNUIdiom) {
9265 if (IsGNUIdiom)
9266 S.Diag(Loc, diag::warn_gnu_null_ptr_arith)
9267 << Pointer->getSourceRange();
9268 else
9269 S.Diag(Loc, diag::warn_pointer_arith_null_ptr)
9270 << S.getLangOpts().CPlusPlus << Pointer->getSourceRange();
9271}
9272
9273/// Diagnose invalid arithmetic on two function pointers.
9274static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc,
9275 Expr *LHS, Expr *RHS) {
9276 assert(LHS->getType()->isAnyPointerType());
9277 assert(RHS->getType()->isAnyPointerType());
9278 S.Diag(Loc, S.getLangOpts().CPlusPlus
9279 ? diag::err_typecheck_pointer_arith_function_type
9280 : diag::ext_gnu_ptr_func_arith)
9281 << 1 /* two pointers */ << LHS->getType()->getPointeeType()
9282 // We only show the second type if it differs from the first.
9283 << (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(),
9284 RHS->getType())
9285 << RHS->getType()->getPointeeType()
9286 << LHS->getSourceRange() << RHS->getSourceRange();
9287}
9288
9289/// Diagnose invalid arithmetic on a function pointer.
9290static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc,
9291 Expr *Pointer) {
9292 assert(Pointer->getType()->isAnyPointerType());
9293 S.Diag(Loc, S.getLangOpts().CPlusPlus
9294 ? diag::err_typecheck_pointer_arith_function_type
9295 : diag::ext_gnu_ptr_func_arith)
9296 << 0 /* one pointer */ << Pointer->getType()->getPointeeType()
9297 << 0 /* one pointer, so only one type */
9298 << Pointer->getSourceRange();
9299}
9300
9301/// Emit error if Operand is incomplete pointer type
9302///
9303/// \returns True if pointer has incomplete type
9304static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc,
9305 Expr *Operand) {
9306 QualType ResType = Operand->getType();
9307 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
9308 ResType = ResAtomicType->getValueType();
9309
9310 assert(ResType->isAnyPointerType() && !ResType->isDependentType());
9311 QualType PointeeTy = ResType->getPointeeType();
9312 return S.RequireCompleteType(Loc, PointeeTy,
9313 diag::err_typecheck_arithmetic_incomplete_type,
9314 PointeeTy, Operand->getSourceRange());
9315}
9316
9317/// Check the validity of an arithmetic pointer operand.
9318///
9319/// If the operand has pointer type, this code will check for pointer types
9320/// which are invalid in arithmetic operations. These will be diagnosed
9321/// appropriately, including whether or not the use is supported as an
9322/// extension.
9323///
9324/// \returns True when the operand is valid to use (even if as an extension).
9325static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc,
9326 Expr *Operand) {
9327 QualType ResType = Operand->getType();
9328 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
9329 ResType = ResAtomicType->getValueType();
9330
9331 if (!ResType->isAnyPointerType()) return true;
9332
9333 QualType PointeeTy = ResType->getPointeeType();
9334 if (PointeeTy->isVoidType()) {
9335 diagnoseArithmeticOnVoidPointer(S, Loc, Operand);
9336 return !S.getLangOpts().CPlusPlus;
9337 }
9338 if (PointeeTy->isFunctionType()) {
9339 diagnoseArithmeticOnFunctionPointer(S, Loc, Operand);
9340 return !S.getLangOpts().CPlusPlus;
9341 }
9342
9343 if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false;
9344
9345 return true;
9346}
9347
9348/// Check the validity of a binary arithmetic operation w.r.t. pointer
9349/// operands.
9350///
9351/// This routine will diagnose any invalid arithmetic on pointer operands much
9352/// like \see checkArithmeticOpPointerOperand. However, it has special logic
9353/// for emitting a single diagnostic even for operations where both LHS and RHS
9354/// are (potentially problematic) pointers.
9355///
9356/// \returns True when the operand is valid to use (even if as an extension).
9357static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc,
9358 Expr *LHSExpr, Expr *RHSExpr) {
9359 bool isLHSPointer = LHSExpr->getType()->isAnyPointerType();
9360 bool isRHSPointer = RHSExpr->getType()->isAnyPointerType();
9361 if (!isLHSPointer && !isRHSPointer) return true;
9362
9363 QualType LHSPointeeTy, RHSPointeeTy;
9364 if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType();
9365 if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType();
9366
9367 // if both are pointers check if operation is valid wrt address spaces
9368 if (S.getLangOpts().OpenCL && isLHSPointer && isRHSPointer) {
9369 const PointerType *lhsPtr = LHSExpr->getType()->getAs<PointerType>();
9370 const PointerType *rhsPtr = RHSExpr->getType()->getAs<PointerType>();
9371 ASTContext &Context = S.getASTContext();
9372 const Expr::NullPointerConstantKind LHSNullKind =
9373 LHSExpr->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
9374 const Expr::NullPointerConstantKind RHSNullKind =
9375 RHSExpr->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
9376 bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
9377 bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
9378 if (!RHSIsNull && !LHSIsNull &&
9379 !lhsPtr->isAddressSpaceOverlapping(*rhsPtr)) {
9380 S.Diag(Loc,
9381 diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
9382 << LHSExpr->getType() << RHSExpr->getType() << 1 /*arithmetic op*/
9383 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
9384 return false;
9385 }
9386 }
9387
9388 // Check for arithmetic on pointers to incomplete types.
9389 bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType();
9390 bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType();
9391 if (isLHSVoidPtr || isRHSVoidPtr) {
9392 if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr);
9393 else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr);
9394 else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr);
9395
9396 return !S.getLangOpts().CPlusPlus;
9397 }
9398
9399 bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType();
9400 bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType();
9401 if (isLHSFuncPtr || isRHSFuncPtr) {
9402 if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr);
9403 else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc,
9404 RHSExpr);
9405 else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr);
9406
9407 return !S.getLangOpts().CPlusPlus;
9408 }
9409
9410 if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, LHSExpr))
9411 return false;
9412 if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, RHSExpr))
9413 return false;
9414
9415 return true;
9416}
9417
9418/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string
9419/// literal.
9420static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc,
9421 Expr *LHSExpr, Expr *RHSExpr) {
9422 StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts());
9423 Expr* IndexExpr = RHSExpr;
9424 if (!StrExpr) {
9425 StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts());
9426 IndexExpr = LHSExpr;
9427 }
9428
9429 bool IsStringPlusInt = StrExpr &&
9430 IndexExpr->getType()->isIntegralOrUnscopedEnumerationType();
9431 if (!IsStringPlusInt || IndexExpr->isValueDependent())
9432 return;
9433
9434 SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
9435 Self.Diag(OpLoc, diag::warn_string_plus_int)
9436 << DiagRange << IndexExpr->IgnoreImpCasts()->getType();
9437
9438 // Only print a fixit for "str" + int, not for int + "str".
9439 if (IndexExpr == RHSExpr) {
9440 SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getEndLoc());
9441 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
9442 << FixItHint::CreateInsertion(LHSExpr->getBeginLoc(), "&")
9443 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
9444 << FixItHint::CreateInsertion(EndLoc, "]");
9445 } else
9446 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
9447}
9448
9449/// Emit a warning when adding a char literal to a string.
9450static void diagnoseStringPlusChar(Sema &Self, SourceLocation OpLoc,
9451 Expr *LHSExpr, Expr *RHSExpr) {
9452 const Expr *StringRefExpr = LHSExpr;
9453 const CharacterLiteral *CharExpr =
9454 dyn_cast<CharacterLiteral>(RHSExpr->IgnoreImpCasts());
9455
9456 if (!CharExpr) {
9457 CharExpr = dyn_cast<CharacterLiteral>(LHSExpr->IgnoreImpCasts());
9458 StringRefExpr = RHSExpr;
9459 }
9460
9461 if (!CharExpr || !StringRefExpr)
9462 return;
9463
9464 const QualType StringType = StringRefExpr->getType();
9465
9466 // Return if not a PointerType.
9467 if (!StringType->isAnyPointerType())
9468 return;
9469
9470 // Return if not a CharacterType.
9471 if (!StringType->getPointeeType()->isAnyCharacterType())
9472 return;
9473
9474 ASTContext &Ctx = Self.getASTContext();
9475 SourceRange DiagRange(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
9476
9477 const QualType CharType = CharExpr->getType();
9478 if (!CharType->isAnyCharacterType() &&
9479 CharType->isIntegerType() &&
9480 llvm::isUIntN(Ctx.getCharWidth(), CharExpr->getValue())) {
9481 Self.Diag(OpLoc, diag::warn_string_plus_char)
9482 << DiagRange << Ctx.CharTy;
9483 } else {
9484 Self.Diag(OpLoc, diag::warn_string_plus_char)
9485 << DiagRange << CharExpr->getType();
9486 }
9487
9488 // Only print a fixit for str + char, not for char + str.
9489 if (isa<CharacterLiteral>(RHSExpr->IgnoreImpCasts())) {
9490 SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getEndLoc());
9491 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
9492 << FixItHint::CreateInsertion(LHSExpr->getBeginLoc(), "&")
9493 << FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
9494 << FixItHint::CreateInsertion(EndLoc, "]");
9495 } else {
9496 Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
9497 }
9498}
9499
9500/// Emit error when two pointers are incompatible.
9501static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc,
9502 Expr *LHSExpr, Expr *RHSExpr) {
9503 assert(LHSExpr->getType()->isAnyPointerType());
9504 assert(RHSExpr->getType()->isAnyPointerType());
9505 S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible)
9506 << LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange()
9507 << RHSExpr->getSourceRange();
9508}
9509
9510// C99 6.5.6
9511QualType Sema::CheckAdditionOperands(ExprResult &LHS, ExprResult &RHS,
9512 SourceLocation Loc, BinaryOperatorKind Opc,
9513 QualType* CompLHSTy) {
9514 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9515
9516 if (LHS.get()->getType()->isVectorType() ||
9517 RHS.get()->getType()->isVectorType()) {
9518 QualType compType = CheckVectorOperands(
9519 LHS, RHS, Loc, CompLHSTy,
9520 /*AllowBothBool*/getLangOpts().AltiVec,
9521 /*AllowBoolConversions*/getLangOpts().ZVector);
9522 if (CompLHSTy) *CompLHSTy = compType;
9523 return compType;
9524 }
9525
9526 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
9527 if (LHS.isInvalid() || RHS.isInvalid())
9528 return QualType();
9529
9530 // Diagnose "string literal" '+' int and string '+' "char literal".
9531 if (Opc == BO_Add) {
9532 diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get());
9533 diagnoseStringPlusChar(*this, Loc, LHS.get(), RHS.get());
9534 }
9535
9536 // handle the common case first (both operands are arithmetic).
9537 if (!compType.isNull() && compType->isArithmeticType()) {
9538 if (CompLHSTy) *CompLHSTy = compType;
9539 return compType;
9540 }
9541
9542 // Type-checking. Ultimately the pointer's going to be in PExp;
9543 // note that we bias towards the LHS being the pointer.
9544 Expr *PExp = LHS.get(), *IExp = RHS.get();
9545
9546 bool isObjCPointer;
9547 if (PExp->getType()->isPointerType()) {
9548 isObjCPointer = false;
9549 } else if (PExp->getType()->isObjCObjectPointerType()) {
9550 isObjCPointer = true;
9551 } else {
9552 std::swap(PExp, IExp);
9553 if (PExp->getType()->isPointerType()) {
9554 isObjCPointer = false;
9555 } else if (PExp->getType()->isObjCObjectPointerType()) {
9556 isObjCPointer = true;
9557 } else {
9558 return InvalidOperands(Loc, LHS, RHS);
9559 }
9560 }
9561 assert(PExp->getType()->isAnyPointerType());
9562
9563 if (!IExp->getType()->isIntegerType())
9564 return InvalidOperands(Loc, LHS, RHS);
9565
9566 // Adding to a null pointer results in undefined behavior.
9567 if (PExp->IgnoreParenCasts()->isNullPointerConstant(
9568 Context, Expr::NPC_ValueDependentIsNotNull)) {
9569 // In C++ adding zero to a null pointer is defined.
9570 Expr::EvalResult KnownVal;
9571 if (!getLangOpts().CPlusPlus ||
9572 (!IExp->isValueDependent() &&
9573 (!IExp->EvaluateAsInt(KnownVal, Context) ||
9574 KnownVal.Val.getInt() != 0))) {
9575 // Check the conditions to see if this is the 'p = nullptr + n' idiom.
9576 bool IsGNUIdiom = BinaryOperator::isNullPointerArithmeticExtension(
9577 Context, BO_Add, PExp, IExp);
9578 diagnoseArithmeticOnNullPointer(*this, Loc, PExp, IsGNUIdiom);
9579 }
9580 }
9581
9582 if (!checkArithmeticOpPointerOperand(*this, Loc, PExp))
9583 return QualType();
9584
9585 if (isObjCPointer && checkArithmeticOnObjCPointer(*this, Loc, PExp))
9586 return QualType();
9587
9588 // Check array bounds for pointer arithemtic
9589 CheckArrayAccess(PExp, IExp);
9590
9591 if (CompLHSTy) {
9592 QualType LHSTy = Context.isPromotableBitField(LHS.get());
9593 if (LHSTy.isNull()) {
9594 LHSTy = LHS.get()->getType();
9595 if (LHSTy->isPromotableIntegerType())
9596 LHSTy = Context.getPromotedIntegerType(LHSTy);
9597 }
9598 *CompLHSTy = LHSTy;
9599 }
9600
9601 return PExp->getType();
9602}
9603
9604// C99 6.5.6
9605QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS,
9606 SourceLocation Loc,
9607 QualType* CompLHSTy) {
9608 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9609
9610 if (LHS.get()->getType()->isVectorType() ||
9611 RHS.get()->getType()->isVectorType()) {
9612 QualType compType = CheckVectorOperands(
9613 LHS, RHS, Loc, CompLHSTy,
9614 /*AllowBothBool*/getLangOpts().AltiVec,
9615 /*AllowBoolConversions*/getLangOpts().ZVector);
9616 if (CompLHSTy) *CompLHSTy = compType;
9617 return compType;
9618 }
9619
9620 QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
9621 if (LHS.isInvalid() || RHS.isInvalid())
9622 return QualType();
9623
9624 // Enforce type constraints: C99 6.5.6p3.
9625
9626 // Handle the common case first (both operands are arithmetic).
9627 if (!compType.isNull() && compType->isArithmeticType()) {
9628 if (CompLHSTy) *CompLHSTy = compType;
9629 return compType;
9630 }
9631
9632 // Either ptr - int or ptr - ptr.
9633 if (LHS.get()->getType()->isAnyPointerType()) {
9634 QualType lpointee = LHS.get()->getType()->getPointeeType();
9635
9636 // Diagnose bad cases where we step over interface counts.
9637 if (LHS.get()->getType()->isObjCObjectPointerType() &&
9638 checkArithmeticOnObjCPointer(*this, Loc, LHS.get()))
9639 return QualType();
9640
9641 // The result type of a pointer-int computation is the pointer type.
9642 if (RHS.get()->getType()->isIntegerType()) {
9643 // Subtracting from a null pointer should produce a warning.
9644 // The last argument to the diagnose call says this doesn't match the
9645 // GNU int-to-pointer idiom.
9646 if (LHS.get()->IgnoreParenCasts()->isNullPointerConstant(Context,
9647 Expr::NPC_ValueDependentIsNotNull)) {
9648 // In C++ adding zero to a null pointer is defined.
9649 Expr::EvalResult KnownVal;
9650 if (!getLangOpts().CPlusPlus ||
9651 (!RHS.get()->isValueDependent() &&
9652 (!RHS.get()->EvaluateAsInt(KnownVal, Context) ||
9653 KnownVal.Val.getInt() != 0))) {
9654 diagnoseArithmeticOnNullPointer(*this, Loc, LHS.get(), false);
9655 }
9656 }
9657
9658 if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get()))
9659 return QualType();
9660
9661 // Check array bounds for pointer arithemtic
9662 CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/nullptr,
9663 /*AllowOnePastEnd*/true, /*IndexNegated*/true);
9664
9665 if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
9666 return LHS.get()->getType();
9667 }
9668
9669 // Handle pointer-pointer subtractions.
9670 if (const PointerType *RHSPTy
9671 = RHS.get()->getType()->getAs<PointerType>()) {
9672 QualType rpointee = RHSPTy->getPointeeType();
9673
9674 if (getLangOpts().CPlusPlus) {
9675 // Pointee types must be the same: C++ [expr.add]
9676 if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) {
9677 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
9678 }
9679 } else {
9680 // Pointee types must be compatible C99 6.5.6p3
9681 if (!Context.typesAreCompatible(
9682 Context.getCanonicalType(lpointee).getUnqualifiedType(),
9683 Context.getCanonicalType(rpointee).getUnqualifiedType())) {
9684 diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
9685 return QualType();
9686 }
9687 }
9688
9689 if (!checkArithmeticBinOpPointerOperands(*this, Loc,
9690 LHS.get(), RHS.get()))
9691 return QualType();
9692
9693 // FIXME: Add warnings for nullptr - ptr.
9694
9695 // The pointee type may have zero size. As an extension, a structure or
9696 // union may have zero size or an array may have zero length. In this
9697 // case subtraction does not make sense.
9698 if (!rpointee->isVoidType() && !rpointee->isFunctionType()) {
9699 CharUnits ElementSize = Context.getTypeSizeInChars(rpointee);
9700 if (ElementSize.isZero()) {
9701 Diag(Loc,diag::warn_sub_ptr_zero_size_types)
9702 << rpointee.getUnqualifiedType()
9703 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9704 }
9705 }
9706
9707 if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
9708 return Context.getPointerDiffType();
9709 }
9710 }
9711
9712 return InvalidOperands(Loc, LHS, RHS);
9713}
9714
9715static bool isScopedEnumerationType(QualType T) {
9716 if (const EnumType *ET = T->getAs<EnumType>())
9717 return ET->getDecl()->isScoped();
9718 return false;
9719}
9720
9721static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS,
9722 SourceLocation Loc, BinaryOperatorKind Opc,
9723 QualType LHSType) {
9724 // OpenCL 6.3j: shift values are effectively % word size of LHS (more defined),
9725 // so skip remaining warnings as we don't want to modify values within Sema.
9726 if (S.getLangOpts().OpenCL)
9727 return;
9728
9729 // Check right/shifter operand
9730 Expr::EvalResult RHSResult;
9731 if (RHS.get()->isValueDependent() ||
9732 !RHS.get()->EvaluateAsInt(RHSResult, S.Context))
9733 return;
9734 llvm::APSInt Right = RHSResult.Val.getInt();
9735
9736 if (Right.isNegative()) {
9737 S.DiagRuntimeBehavior(Loc, RHS.get(),
9738 S.PDiag(diag::warn_shift_negative)
9739 << RHS.get()->getSourceRange());
9740 return;
9741 }
9742 llvm::APInt LeftBits(Right.getBitWidth(),
9743 S.Context.getTypeSize(LHS.get()->getType()));
9744 if (Right.uge(LeftBits)) {
9745 S.DiagRuntimeBehavior(Loc, RHS.get(),
9746 S.PDiag(diag::warn_shift_gt_typewidth)
9747 << RHS.get()->getSourceRange());
9748 return;
9749 }
9750 if (Opc != BO_Shl)
9751 return;
9752
9753 // When left shifting an ICE which is signed, we can check for overflow which
9754 // according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned
9755 // integers have defined behavior modulo one more than the maximum value
9756 // representable in the result type, so never warn for those.
9757 Expr::EvalResult LHSResult;
9758 if (LHS.get()->isValueDependent() ||
9759 LHSType->hasUnsignedIntegerRepresentation() ||
9760 !LHS.get()->EvaluateAsInt(LHSResult, S.Context))
9761 return;
9762 llvm::APSInt Left = LHSResult.Val.getInt();
9763
9764 // If LHS does not have a signed type and non-negative value
9765 // then, the behavior is undefined. Warn about it.
9766 if (Left.isNegative() && !S.getLangOpts().isSignedOverflowDefined()) {
9767 S.DiagRuntimeBehavior(Loc, LHS.get(),
9768 S.PDiag(diag::warn_shift_lhs_negative)
9769 << LHS.get()->getSourceRange());
9770 return;
9771 }
9772
9773 llvm::APInt ResultBits =
9774 static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits();
9775 if (LeftBits.uge(ResultBits))
9776 return;
9777 llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue());
9778 Result = Result.shl(Right);
9779
9780 // Print the bit representation of the signed integer as an unsigned
9781 // hexadecimal number.
9782 SmallString<40> HexResult;
9783 Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true);
9784
9785 // If we are only missing a sign bit, this is less likely to result in actual
9786 // bugs -- if the result is cast back to an unsigned type, it will have the
9787 // expected value. Thus we place this behind a different warning that can be
9788 // turned off separately if needed.
9789 if (LeftBits == ResultBits - 1) {
9790 S.Diag(Loc, diag::warn_shift_result_sets_sign_bit)
9791 << HexResult << LHSType
9792 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9793 return;
9794 }
9795
9796 S.Diag(Loc, diag::warn_shift_result_gt_typewidth)
9797 << HexResult.str() << Result.getMinSignedBits() << LHSType
9798 << Left.getBitWidth() << LHS.get()->getSourceRange()
9799 << RHS.get()->getSourceRange();
9800}
9801
9802/// Return the resulting type when a vector is shifted
9803/// by a scalar or vector shift amount.
9804static QualType checkVectorShift(Sema &S, ExprResult &LHS, ExprResult &RHS,
9805 SourceLocation Loc, bool IsCompAssign) {
9806 // OpenCL v1.1 s6.3.j says RHS can be a vector only if LHS is a vector.
9807 if ((S.LangOpts.OpenCL || S.LangOpts.ZVector) &&
9808 !LHS.get()->getType()->isVectorType()) {
9809 S.Diag(Loc, diag::err_shift_rhs_only_vector)
9810 << RHS.get()->getType() << LHS.get()->getType()
9811 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9812 return QualType();
9813 }
9814
9815 if (!IsCompAssign) {
9816 LHS = S.UsualUnaryConversions(LHS.get());
9817 if (LHS.isInvalid()) return QualType();
9818 }
9819
9820 RHS = S.UsualUnaryConversions(RHS.get());
9821 if (RHS.isInvalid()) return QualType();
9822
9823 QualType LHSType = LHS.get()->getType();
9824 // Note that LHS might be a scalar because the routine calls not only in
9825 // OpenCL case.
9826 const VectorType *LHSVecTy = LHSType->getAs<VectorType>();
9827 QualType LHSEleType = LHSVecTy ? LHSVecTy->getElementType() : LHSType;
9828
9829 // Note that RHS might not be a vector.
9830 QualType RHSType = RHS.get()->getType();
9831 const VectorType *RHSVecTy = RHSType->getAs<VectorType>();
9832 QualType RHSEleType = RHSVecTy ? RHSVecTy->getElementType() : RHSType;
9833
9834 // The operands need to be integers.
9835 if (!LHSEleType->isIntegerType()) {
9836 S.Diag(Loc, diag::err_typecheck_expect_int)
9837 << LHS.get()->getType() << LHS.get()->getSourceRange();
9838 return QualType();
9839 }
9840
9841 if (!RHSEleType->isIntegerType()) {
9842 S.Diag(Loc, diag::err_typecheck_expect_int)
9843 << RHS.get()->getType() << RHS.get()->getSourceRange();
9844 return QualType();
9845 }
9846
9847 if (!LHSVecTy) {
9848 assert(RHSVecTy);
9849 if (IsCompAssign)
9850 return RHSType;
9851 if (LHSEleType != RHSEleType) {
9852 LHS = S.ImpCastExprToType(LHS.get(),RHSEleType, CK_IntegralCast);
9853 LHSEleType = RHSEleType;
9854 }
9855 QualType VecTy =
9856 S.Context.getExtVectorType(LHSEleType, RHSVecTy->getNumElements());
9857 LHS = S.ImpCastExprToType(LHS.get(), VecTy, CK_VectorSplat);
9858 LHSType = VecTy;
9859 } else if (RHSVecTy) {
9860 // OpenCL v1.1 s6.3.j says that for vector types, the operators
9861 // are applied component-wise. So if RHS is a vector, then ensure
9862 // that the number of elements is the same as LHS...
9863 if (RHSVecTy->getNumElements() != LHSVecTy->getNumElements()) {
9864 S.Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
9865 << LHS.get()->getType() << RHS.get()->getType()
9866 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9867 return QualType();
9868 }
9869 if (!S.LangOpts.OpenCL && !S.LangOpts.ZVector) {
9870 const BuiltinType *LHSBT = LHSEleType->getAs<clang::BuiltinType>();
9871 const BuiltinType *RHSBT = RHSEleType->getAs<clang::BuiltinType>();
9872 if (LHSBT != RHSBT &&
9873 S.Context.getTypeSize(LHSBT) != S.Context.getTypeSize(RHSBT)) {
9874 S.Diag(Loc, diag::warn_typecheck_vector_element_sizes_not_equal)
9875 << LHS.get()->getType() << RHS.get()->getType()
9876 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9877 }
9878 }
9879 } else {
9880 // ...else expand RHS to match the number of elements in LHS.
9881 QualType VecTy =
9882 S.Context.getExtVectorType(RHSEleType, LHSVecTy->getNumElements());
9883 RHS = S.ImpCastExprToType(RHS.get(), VecTy, CK_VectorSplat);
9884 }
9885
9886 return LHSType;
9887}
9888
9889// C99 6.5.7
9890QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS,
9891 SourceLocation Loc, BinaryOperatorKind Opc,
9892 bool IsCompAssign) {
9893 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
9894
9895 // Vector shifts promote their scalar inputs to vector type.
9896 if (LHS.get()->getType()->isVectorType() ||
9897 RHS.get()->getType()->isVectorType()) {
9898 if (LangOpts.ZVector) {
9899 // The shift operators for the z vector extensions work basically
9900 // like general shifts, except that neither the LHS nor the RHS is
9901 // allowed to be a "vector bool".
9902 if (auto LHSVecType = LHS.get()->getType()->getAs<VectorType>())
9903 if (LHSVecType->getVectorKind() == VectorType::AltiVecBool)
9904 return InvalidOperands(Loc, LHS, RHS);
9905 if (auto RHSVecType = RHS.get()->getType()->getAs<VectorType>())
9906 if (RHSVecType->getVectorKind() == VectorType::AltiVecBool)
9907 return InvalidOperands(Loc, LHS, RHS);
9908 }
9909 return checkVectorShift(*this, LHS, RHS, Loc, IsCompAssign);
9910 }
9911
9912 // Shifts don't perform usual arithmetic conversions, they just do integer
9913 // promotions on each operand. C99 6.5.7p3
9914
9915 // For the LHS, do usual unary conversions, but then reset them away
9916 // if this is a compound assignment.
9917 ExprResult OldLHS = LHS;
9918 LHS = UsualUnaryConversions(LHS.get());
9919 if (LHS.isInvalid())
9920 return QualType();
9921 QualType LHSType = LHS.get()->getType();
9922 if (IsCompAssign) LHS = OldLHS;
9923
9924 // The RHS is simpler.
9925 RHS = UsualUnaryConversions(RHS.get());
9926 if (RHS.isInvalid())
9927 return QualType();
9928 QualType RHSType = RHS.get()->getType();
9929
9930 // C99 6.5.7p2: Each of the operands shall have integer type.
9931 if (!LHSType->hasIntegerRepresentation() ||
9932 !RHSType->hasIntegerRepresentation())
9933 return InvalidOperands(Loc, LHS, RHS);
9934
9935 // C++0x: Don't allow scoped enums. FIXME: Use something better than
9936 // hasIntegerRepresentation() above instead of this.
9937 if (isScopedEnumerationType(LHSType) ||
9938 isScopedEnumerationType(RHSType)) {
9939 return InvalidOperands(Loc, LHS, RHS);
9940 }
9941 // Sanity-check shift operands
9942 DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType);
9943
9944 // In CHERI offset mode shifts only look at the offset and ignore the base.
9945 // This is rarely the intended behaviour so warn if that is the case.
9946 if (getLangOpts().cheriUIntCapUsesOffset() &&
9947 (LHSType->isIntCapType() || RHSType->isIntCapType()) &&
9948 (Opc == BO_Shl || Opc == BO_ShlAssign || Opc == BO_Shr ||
9949 Opc == BO_ShrAssign))
9950 DiagRuntimeBehavior(Loc, RHS.get(),
9951 PDiag(diag::warn_uintcap_bad_bitwise_op)
9952 << 1 /*=shift*/ << 0 /* usecase is hashing */
9953 << LHS.get()->getSourceRange()
9954 << RHS.get()->getSourceRange());
9955
9956 // "The type of the result is that of the promoted left operand."
9957 return LHSType;
9958}
9959
9960/// If two different enums are compared, raise a warning.
9961static void checkEnumComparison(Sema &S, SourceLocation Loc, Expr *LHS,
9962 Expr *RHS) {
9963 QualType LHSStrippedType = LHS->IgnoreParenImpCasts()->getType();
9964 QualType RHSStrippedType = RHS->IgnoreParenImpCasts()->getType();
9965
9966 const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>();
9967 if (!LHSEnumType)
9968 return;
9969 const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>();
9970 if (!RHSEnumType)
9971 return;
9972
9973 // Ignore anonymous enums.
9974 if (!LHSEnumType->getDecl()->getIdentifier() &&
9975 !LHSEnumType->getDecl()->getTypedefNameForAnonDecl())
9976 return;
9977 if (!RHSEnumType->getDecl()->getIdentifier() &&
9978 !RHSEnumType->getDecl()->getTypedefNameForAnonDecl())
9979 return;
9980
9981 if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType))
9982 return;
9983
9984 S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types)
9985 << LHSStrippedType << RHSStrippedType
9986 << LHS->getSourceRange() << RHS->getSourceRange();
9987}
9988
9989/// Diagnose bad pointer comparisons.
9990static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc,
9991 ExprResult &LHS, ExprResult &RHS,
9992 bool IsError) {
9993 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers
9994 : diag::ext_typecheck_comparison_of_distinct_pointers)
9995 << LHS.get()->getType() << RHS.get()->getType()
9996 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
9997}
9998
9999/// Returns false if the pointers are converted to a composite type,
10000/// true otherwise.
10001static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc,
10002 ExprResult &LHS, ExprResult &RHS) {
10003 // C++ [expr.rel]p2:
10004 // [...] Pointer conversions (4.10) and qualification
10005 // conversions (4.4) are performed on pointer operands (or on
10006 // a pointer operand and a null pointer constant) to bring
10007 // them to their composite pointer type. [...]
10008 //
10009 // C++ [expr.eq]p1 uses the same notion for (in)equality
10010 // comparisons of pointers.
10011
10012 QualType LHSType = LHS.get()->getType();
10013 QualType RHSType = RHS.get()->getType();
10014 assert(LHSType->isPointerType() || RHSType->isPointerType() ||
10015 LHSType->isMemberPointerType() || RHSType->isMemberPointerType());
10016
10017 QualType T = S.FindCompositePointerType(Loc, LHS, RHS);
10018 if (T.isNull()) {
10019 if ((LHSType->isPointerType() || LHSType->isMemberPointerType()) &&
10020 (RHSType->isPointerType() || RHSType->isMemberPointerType()))
10021 diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true);
10022 else
10023 S.InvalidOperands(Loc, LHS, RHS);
10024 return true;
10025 }
10026
10027 LHS = S.ImpCastExprToType(LHS.get(), T, CK_BitCast);
10028 RHS = S.ImpCastExprToType(RHS.get(), T, CK_BitCast);
10029 return false;
10030}
10031
10032static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc,
10033 ExprResult &LHS,
10034 ExprResult &RHS,
10035 bool IsError) {
10036 S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void
10037 : diag::ext_typecheck_comparison_of_fptr_to_void)
10038 << LHS.get()->getType() << RHS.get()->getType()
10039 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10040}
10041
10042static bool isObjCObjectLiteral(ExprResult &E) {
10043 switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) {
10044 case Stmt::ObjCArrayLiteralClass:
10045 case Stmt::ObjCDictionaryLiteralClass:
10046 case Stmt::ObjCStringLiteralClass:
10047 case Stmt::ObjCBoxedExprClass:
10048 return true;
10049 default:
10050 // Note that ObjCBoolLiteral is NOT an object literal!
10051 return false;
10052 }
10053}
10054
10055static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) {
10056 const ObjCObjectPointerType *Type =
10057 LHS->getType()->getAs<ObjCObjectPointerType>();
10058
10059 // If this is not actually an Objective-C object, bail out.
10060 if (!Type)
10061 return false;
10062
10063 // Get the LHS object's interface type.
10064 QualType InterfaceType = Type->getPointeeType();
10065
10066 // If the RHS isn't an Objective-C object, bail out.
10067 if (!RHS->getType()->isObjCObjectPointerType())
10068 return false;
10069
10070 // Try to find the -isEqual: method.
10071 Selector IsEqualSel = S.NSAPIObj->getIsEqualSelector();
10072 ObjCMethodDecl *Method = S.LookupMethodInObjectType(IsEqualSel,
10073 InterfaceType,
10074 /*instance=*/true);
10075 if (!Method) {
10076 if (Type->isObjCIdType()) {
10077 // For 'id', just check the global pool.
10078 Method = S.LookupInstanceMethodInGlobalPool(IsEqualSel, SourceRange(),
10079 /*receiverId=*/true);
10080 } else {
10081 // Check protocols.
10082 Method = S.LookupMethodInQualifiedType(IsEqualSel, Type,
10083 /*instance=*/true);
10084 }
10085 }
10086
10087 if (!Method)
10088 return false;
10089
10090 QualType T = Method->parameters()[0]->getType();
10091 if (!T->isObjCObjectPointerType())
10092 return false;
10093
10094 QualType R = Method->getReturnType();
10095 if (!R->isScalarType())
10096 return false;
10097
10098 return true;
10099}
10100
10101Sema::ObjCLiteralKind Sema::CheckLiteralKind(Expr *FromE) {
10102 FromE = FromE->IgnoreParenImpCasts();
10103 switch (FromE->getStmtClass()) {
10104 default:
10105 break;
10106 case Stmt::ObjCStringLiteralClass:
10107 // "string literal"
10108 return LK_String;
10109 case Stmt::ObjCArrayLiteralClass:
10110 // "array literal"
10111 return LK_Array;
10112 case Stmt::ObjCDictionaryLiteralClass:
10113 // "dictionary literal"
10114 return LK_Dictionary;
10115 case Stmt::BlockExprClass:
10116 return LK_Block;
10117 case Stmt::ObjCBoxedExprClass: {
10118 Expr *Inner = cast<ObjCBoxedExpr>(FromE)->getSubExpr()->IgnoreParens();
10119 switch (Inner->getStmtClass()) {
10120 case Stmt::IntegerLiteralClass:
10121 case Stmt::FloatingLiteralClass:
10122 case Stmt::CharacterLiteralClass:
10123 case Stmt::ObjCBoolLiteralExprClass:
10124 case Stmt::CXXBoolLiteralExprClass:
10125 // "numeric literal"
10126 return LK_Numeric;
10127 case Stmt::ImplicitCastExprClass: {
10128 CastKind CK = cast<CastExpr>(Inner)->getCastKind();
10129 // Boolean literals can be represented by implicit casts.
10130 if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast)
10131 return LK_Numeric;
10132 break;
10133 }
10134 default:
10135 break;
10136 }
10137 return LK_Boxed;
10138 }
10139 }
10140 return LK_None;
10141}
10142
10143static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
10144 ExprResult &LHS, ExprResult &RHS,
10145 BinaryOperator::Opcode Opc){
10146 Expr *Literal;
10147 Expr *Other;
10148 if (isObjCObjectLiteral(LHS)) {
10149 Literal = LHS.get();
10150 Other = RHS.get();
10151 } else {
10152 Literal = RHS.get();
10153 Other = LHS.get();
10154 }
10155
10156 // Don't warn on comparisons against nil.
10157 Other = Other->IgnoreParenCasts();
10158 if (Other->isNullPointerConstant(S.getASTContext(),
10159 Expr::NPC_ValueDependentIsNotNull))
10160 return;
10161
10162 // This should be kept in sync with warn_objc_literal_comparison.
10163 // LK_String should always be after the other literals, since it has its own
10164 // warning flag.
10165 Sema::ObjCLiteralKind LiteralKind = S.CheckLiteralKind(Literal);
10166 assert(LiteralKind != Sema::LK_Block);
10167 if (LiteralKind == Sema::LK_None) {
10168 llvm_unreachable("Unknown Objective-C object literal kind");
10169 }
10170
10171 if (LiteralKind == Sema::LK_String)
10172 S.Diag(Loc, diag::warn_objc_string_literal_comparison)
10173 << Literal->getSourceRange();
10174 else
10175 S.Diag(Loc, diag::warn_objc_literal_comparison)
10176 << LiteralKind << Literal->getSourceRange();
10177
10178 if (BinaryOperator::isEqualityOp(Opc) &&
10179 hasIsEqualMethod(S, LHS.get(), RHS.get())) {
10180 SourceLocation Start = LHS.get()->getBeginLoc();
10181 SourceLocation End = S.getLocForEndOfToken(RHS.get()->getEndLoc());
10182 CharSourceRange OpRange =
10183 CharSourceRange::getCharRange(Loc, S.getLocForEndOfToken(Loc));
10184
10185 S.Diag(Loc, diag::note_objc_literal_comparison_isequal)
10186 << FixItHint::CreateInsertion(Start, Opc == BO_EQ ? "[" : "![")
10187 << FixItHint::CreateReplacement(OpRange, " isEqual:")
10188 << FixItHint::CreateInsertion(End, "]");
10189 }
10190}
10191
10192/// Warns on !x < y, !x & y where !(x < y), !(x & y) was probably intended.
10193static void diagnoseLogicalNotOnLHSofCheck(Sema &S, ExprResult &LHS,
10194 ExprResult &RHS, SourceLocation Loc,
10195 BinaryOperatorKind Opc) {
10196 // Check that left hand side is !something.
10197 UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS.get()->IgnoreImpCasts());
10198 if (!UO || UO->getOpcode() != UO_LNot) return;
10199
10200 // Only check if the right hand side is non-bool arithmetic type.
10201 if (RHS.get()->isKnownToHaveBooleanValue()) return;
10202
10203 // Make sure that the something in !something is not bool.
10204 Expr *SubExpr = UO->getSubExpr()->IgnoreImpCasts();
10205 if (SubExpr->isKnownToHaveBooleanValue()) return;
10206
10207 // Emit warning.
10208 bool IsBitwiseOp = Opc == BO_And || Opc == BO_Or || Opc == BO_Xor;
10209 S.Diag(UO->getOperatorLoc(), diag::warn_logical_not_on_lhs_of_check)
10210 << Loc << IsBitwiseOp;
10211
10212 // First note suggest !(x < y)
10213 SourceLocation FirstOpen = SubExpr->getBeginLoc();
10214 SourceLocation FirstClose = RHS.get()->getEndLoc();
10215 FirstClose = S.getLocForEndOfToken(FirstClose);
10216 if (FirstClose.isInvalid())
10217 FirstOpen = SourceLocation();
10218 S.Diag(UO->getOperatorLoc(), diag::note_logical_not_fix)
10219 << IsBitwiseOp
10220 << FixItHint::CreateInsertion(FirstOpen, "(")
10221 << FixItHint::CreateInsertion(FirstClose, ")");
10222
10223 // Second note suggests (!x) < y
10224 SourceLocation SecondOpen = LHS.get()->getBeginLoc();
10225 SourceLocation SecondClose = LHS.get()->getEndLoc();
10226 SecondClose = S.getLocForEndOfToken(SecondClose);
10227 if (SecondClose.isInvalid())
10228 SecondOpen = SourceLocation();
10229 S.Diag(UO->getOperatorLoc(), diag::note_logical_not_silence_with_parens)
10230 << FixItHint::CreateInsertion(SecondOpen, "(")
10231 << FixItHint::CreateInsertion(SecondClose, ")");
10232}
10233
10234// Get the decl for a simple expression: a reference to a variable,
10235// an implicit C++ field reference, or an implicit ObjC ivar reference.
10236static ValueDecl *getCompareDecl(Expr *E) {
10237 if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E))
10238 return DR->getDecl();
10239 if (ObjCIvarRefExpr *Ivar = dyn_cast<ObjCIvarRefExpr>(E)) {
10240 if (Ivar->isFreeIvar())
10241 return Ivar->getDecl();
10242 }
10243 if (MemberExpr *Mem = dyn_cast<MemberExpr>(E)) {
10244 if (Mem->isImplicitAccess())
10245 return Mem->getMemberDecl();
10246 }
10247 return nullptr;
10248}
10249
10250/// Diagnose some forms of syntactically-obvious tautological comparison.
10251static void diagnoseTautologicalComparison(Sema &S, SourceLocation Loc,
10252 Expr *LHS, Expr *RHS,
10253 BinaryOperatorKind Opc) {
10254 Expr *LHSStripped = LHS->IgnoreParenImpCasts();
10255 Expr *RHSStripped = RHS->IgnoreParenImpCasts();
10256
10257 QualType LHSType = LHS->getType();
10258 QualType RHSType = RHS->getType();
10259 if (LHSType->hasFloatingRepresentation() ||
10260 (LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)) ||
10261 LHS->getBeginLoc().isMacroID() || RHS->getBeginLoc().isMacroID() ||
10262 S.inTemplateInstantiation())
10263 return;
10264
10265 // Comparisons between two array types are ill-formed for operator<=>, so
10266 // we shouldn't emit any additional warnings about it.
10267 if (Opc == BO_Cmp && LHSType->isArrayType() && RHSType->isArrayType())
10268 return;
10269
10270 // For non-floating point types, check for self-comparisons of the form
10271 // x == x, x != x, x < x, etc. These always evaluate to a constant, and
10272 // often indicate logic errors in the program.
10273 //
10274 // NOTE: Don't warn about comparison expressions resulting from macro
10275 // expansion. Also don't warn about comparisons which are only self
10276 // comparisons within a template instantiation. The warnings should catch
10277 // obvious cases in the definition of the template anyways. The idea is to
10278 // warn when the typed comparison operator will always evaluate to the same
10279 // result.
10280 ValueDecl *DL = getCompareDecl(LHSStripped);
10281 ValueDecl *DR = getCompareDecl(RHSStripped);
10282 if (DL && DR && declaresSameEntity(DL, DR)) {
10283 StringRef Result;
10284 switch (Opc) {
10285 case BO_EQ: case BO_LE: case BO_GE:
10286 Result = "true";
10287 break;
10288 case BO_NE: case BO_LT: case BO_GT:
10289 Result = "false";
10290 break;
10291 case BO_Cmp:
10292 Result = "'std::strong_ordering::equal'";
10293 break;
10294 default:
10295 break;
10296 }
10297 S.DiagRuntimeBehavior(Loc, nullptr,
10298 S.PDiag(diag::warn_comparison_always)
10299 << 0 /*self-comparison*/ << !Result.empty()
10300 << Result);
10301 } else if (DL && DR &&
10302 DL->getType()->isArrayType() && DR->getType()->isArrayType() &&
10303 !DL->isWeak() && !DR->isWeak()) {
10304 // What is it always going to evaluate to?
10305 StringRef Result;
10306 switch(Opc) {
10307 case BO_EQ: // e.g. array1 == array2
10308 Result = "false";
10309 break;
10310 case BO_NE: // e.g. array1 != array2
10311 Result = "true";
10312 break;
10313 default: // e.g. array1 <= array2
10314 // The best we can say is 'a constant'
10315 break;
10316 }
10317 S.DiagRuntimeBehavior(Loc, nullptr,
10318 S.PDiag(diag::warn_comparison_always)
10319 << 1 /*array comparison*/
10320 << !Result.empty() << Result);
10321 }
10322
10323 if (isa<CastExpr>(LHSStripped))
10324 LHSStripped = LHSStripped->IgnoreParenCasts();
10325 if (isa<CastExpr>(RHSStripped))
10326 RHSStripped = RHSStripped->IgnoreParenCasts();
10327
10328 // Warn about comparisons against a string constant (unless the other
10329 // operand is null); the user probably wants strcmp.
10330 Expr *LiteralString = nullptr;
10331 Expr *LiteralStringStripped = nullptr;
10332 if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) &&
10333 !RHSStripped->isNullPointerConstant(S.Context,
10334 Expr::NPC_ValueDependentIsNull)) {
10335 LiteralString = LHS;
10336 LiteralStringStripped = LHSStripped;
10337 } else if ((isa<StringLiteral>(RHSStripped) ||
10338 isa<ObjCEncodeExpr>(RHSStripped)) &&
10339 !LHSStripped->isNullPointerConstant(S.Context,
10340 Expr::NPC_ValueDependentIsNull)) {
10341 LiteralString = RHS;
10342 LiteralStringStripped = RHSStripped;
10343 }
10344
10345 if (LiteralString) {
10346 S.DiagRuntimeBehavior(Loc, nullptr,
10347 S.PDiag(diag::warn_stringcompare)
10348 << isa<ObjCEncodeExpr>(LiteralStringStripped)
10349 << LiteralString->getSourceRange());
10350 }
10351}
10352
10353static ImplicitConversionKind castKindToImplicitConversionKind(CastKind CK) {
10354 switch (CK) {
10355 default: {
10356#ifndef NDEBUG
10357 llvm::errs() << "unhandled cast kind: " << CastExpr::getCastKindName(CK)
10358 << "\n";
10359#endif
10360 llvm_unreachable("unhandled cast kind");
10361 }
10362 case CK_UserDefinedConversion:
10363 return ICK_Identity;
10364 case CK_LValueToRValue:
10365 return ICK_Lvalue_To_Rvalue;
10366 case CK_ArrayToPointerDecay:
10367 return ICK_Array_To_Pointer;
10368 case CK_FunctionToPointerDecay:
10369 return ICK_Function_To_Pointer;
10370 case CK_IntegralCast:
10371 return ICK_Integral_Conversion;
10372 case CK_FloatingCast:
10373 return ICK_Floating_Conversion;
10374 case CK_IntegralToFloating:
10375 case CK_FloatingToIntegral:
10376 return ICK_Floating_Integral;
10377 case CK_IntegralComplexCast:
10378 case CK_FloatingComplexCast:
10379 case CK_FloatingComplexToIntegralComplex:
10380 case CK_IntegralComplexToFloatingComplex:
10381 return ICK_Complex_Conversion;
10382 case CK_FloatingComplexToReal:
10383 case CK_FloatingRealToComplex:
10384 case CK_IntegralComplexToReal:
10385 case CK_IntegralRealToComplex:
10386 return ICK_Complex_Real;
10387 }
10388}
10389
10390static bool checkThreeWayNarrowingConversion(Sema &S, QualType ToType, Expr *E,
10391 QualType FromType,
10392 SourceLocation Loc) {
10393 // Check for a narrowing implicit conversion.
10394 StandardConversionSequence SCS;
10395 SCS.setAsIdentityConversion();
10396 SCS.setToType(0, FromType);
10397 SCS.setToType(1, ToType);
10398 if (const auto *ICE = dyn_cast<ImplicitCastExpr>(E))
10399 SCS.Second = castKindToImplicitConversionKind(ICE->getCastKind());
10400
10401 APValue PreNarrowingValue;
10402 QualType PreNarrowingType;
10403 switch (SCS.getNarrowingKind(S.Context, E, PreNarrowingValue,
10404 PreNarrowingType,
10405 /*IgnoreFloatToIntegralConversion*/ true)) {
10406 case NK_Dependent_Narrowing:
10407 // Implicit conversion to a narrower type, but the expression is
10408 // value-dependent so we can't tell whether it's actually narrowing.
10409 case NK_Not_Narrowing:
10410 return false;
10411
10412 case NK_Constant_Narrowing:
10413 // Implicit conversion to a narrower type, and the value is not a constant
10414 // expression.
10415 S.Diag(E->getBeginLoc(), diag::err_spaceship_argument_narrowing)
10416 << /*Constant*/ 1
10417 << PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << ToType;
10418 return true;
10419
10420 case NK_Variable_Narrowing:
10421 // Implicit conversion to a narrower type, and the value is not a constant
10422 // expression.
10423 case NK_Type_Narrowing:
10424 S.Diag(E->getBeginLoc(), diag::err_spaceship_argument_narrowing)
10425 << /*Constant*/ 0 << FromType << ToType;
10426 // TODO: It's not a constant expression, but what if the user intended it
10427 // to be? Can we produce notes to help them figure out why it isn't?
10428 return true;
10429 }
10430 llvm_unreachable("unhandled case in switch");
10431}
10432
10433static QualType checkArithmeticOrEnumeralThreeWayCompare(Sema &S,
10434 ExprResult &LHS,
10435 ExprResult &RHS,
10436 SourceLocation Loc) {
10437 using CCT = ComparisonCategoryType;
10438
10439 QualType LHSType = LHS.get()->getType();
10440 QualType RHSType = RHS.get()->getType();
10441 // Dig out the original argument type and expression before implicit casts
10442 // were applied. These are the types/expressions we need to check the
10443 // [expr.spaceship] requirements against.
10444 ExprResult LHSStripped = LHS.get()->IgnoreParenImpCasts();
10445 ExprResult RHSStripped = RHS.get()->IgnoreParenImpCasts();
10446 QualType LHSStrippedType = LHSStripped.get()->getType();
10447 QualType RHSStrippedType = RHSStripped.get()->getType();
10448
10449 // C++2a [expr.spaceship]p3: If one of the operands is of type bool and the
10450 // other is not, the program is ill-formed.
10451 if (LHSStrippedType->isBooleanType() != RHSStrippedType->isBooleanType()) {
10452 S.InvalidOperands(Loc, LHSStripped, RHSStripped);
10453 return QualType();
10454 }
10455
10456 int NumEnumArgs = (int)LHSStrippedType->isEnumeralType() +
10457 RHSStrippedType->isEnumeralType();
10458 if (NumEnumArgs == 1) {
10459 bool LHSIsEnum = LHSStrippedType->isEnumeralType();
10460 QualType OtherTy = LHSIsEnum ? RHSStrippedType : LHSStrippedType;
10461 if (OtherTy->hasFloatingRepresentation()) {
10462 S.InvalidOperands(Loc, LHSStripped, RHSStripped);
10463 return QualType();
10464 }
10465 }
10466 if (NumEnumArgs == 2) {
10467 // C++2a [expr.spaceship]p5: If both operands have the same enumeration
10468 // type E, the operator yields the result of converting the operands
10469 // to the underlying type of E and applying <=> to the converted operands.
10470 if (!S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) {
10471 S.InvalidOperands(Loc, LHS, RHS);
10472 return QualType();
10473 }
10474 QualType IntType =
10475 LHSStrippedType->getAs<EnumType>()->getDecl()->getIntegerType();
10476 assert(IntType->isArithmeticType());
10477
10478 // We can't use `CK_IntegralCast` when the underlying type is 'bool', so we
10479 // promote the boolean type, and all other promotable integer types, to
10480 // avoid this.
10481 if (IntType->isPromotableIntegerType())
10482 IntType = S.Context.getPromotedIntegerType(IntType);
10483
10484 LHS = S.ImpCastExprToType(LHS.get(), IntType, CK_IntegralCast);
10485 RHS = S.ImpCastExprToType(RHS.get(), IntType, CK_IntegralCast);
10486 LHSType = RHSType = IntType;
10487 }
10488
10489 // C++2a [expr.spaceship]p4: If both operands have arithmetic types, the
10490 // usual arithmetic conversions are applied to the operands.
10491 QualType Type = S.UsualArithmeticConversions(LHS, RHS);
10492 if (LHS.isInvalid() || RHS.isInvalid())
10493 return QualType();
10494 if (Type.isNull())
10495 return S.InvalidOperands(Loc, LHS, RHS);
10496 assert(Type->isArithmeticType() || Type->isEnumeralType());
10497
10498 bool HasNarrowing = checkThreeWayNarrowingConversion(
10499 S, Type, LHS.get(), LHSType, LHS.get()->getBeginLoc());
10500 HasNarrowing |= checkThreeWayNarrowingConversion(S, Type, RHS.get(), RHSType,
10501 RHS.get()->getBeginLoc());
10502 if (HasNarrowing)
10503 return QualType();
10504
10505 assert(!Type.isNull() && "composite type for <=> has not been set");
10506
10507 auto TypeKind = [&]() {
10508 if (const ComplexType *CT = Type->getAs<ComplexType>()) {
10509 if (CT->getElementType()->hasFloatingRepresentation())
10510 return CCT::WeakEquality;
10511 return CCT::StrongEquality;
10512 }
10513 if (Type->isIntegralOrEnumerationType())
10514 return CCT::StrongOrdering;
10515 if (Type->hasFloatingRepresentation())
10516 return CCT::PartialOrdering;
10517 llvm_unreachable("other types are unimplemented");
10518 }();
10519
10520 return S.CheckComparisonCategoryType(TypeKind, Loc);
10521}
10522
10523static QualType checkArithmeticOrEnumeralCompare(Sema &S, ExprResult &LHS,
10524 ExprResult &RHS,
10525 SourceLocation Loc,
10526 BinaryOperatorKind Opc) {
10527 if (Opc == BO_Cmp)
10528 return checkArithmeticOrEnumeralThreeWayCompare(S, LHS, RHS, Loc);
10529
10530 // C99 6.5.8p3 / C99 6.5.9p4
10531 QualType Type = S.UsualArithmeticConversions(LHS, RHS);
10532 if (LHS.isInvalid() || RHS.isInvalid())
10533 return QualType();
10534 if (Type.isNull())
10535 return S.InvalidOperands(Loc, LHS, RHS);
10536 assert(Type->isArithmeticType() || Type->isEnumeralType());
10537
10538 checkEnumComparison(S, Loc, LHS.get(), RHS.get());
10539
10540 if (Type->isAnyComplexType() && BinaryOperator::isRelationalOp(Opc))
10541 return S.InvalidOperands(Loc, LHS, RHS);
10542
10543 // Check for comparisons of floating point operands using != and ==.
10544 if (Type->hasFloatingRepresentation() && BinaryOperator::isEqualityOp(Opc))
10545 S.CheckFloatComparison(Loc, LHS.get(), RHS.get());
10546
10547 // The result of comparisons is 'bool' in C++, 'int' in C.
10548 return S.Context.getLogicalOperationType();
10549}
10550
10551// C99 6.5.8, C++ [expr.rel]
10552QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
10553 SourceLocation Loc,
10554 BinaryOperatorKind Opc) {
10555 bool IsRelational = BinaryOperator::isRelationalOp(Opc);
10556 bool IsThreeWay = Opc == BO_Cmp;
10557 auto IsAnyPointerType = [](ExprResult E) {
10558 QualType Ty = E.get()->getType();
10559 return Ty->isPointerType() || Ty->isMemberPointerType();
10560 };
10561
10562 // C++2a [expr.spaceship]p6: If at least one of the operands is of pointer
10563 // type, array-to-pointer, ..., conversions are performed on both operands to
10564 // bring them to their composite type.
10565 // Otherwise, all comparisons expect an rvalue, so convert to rvalue before
10566 // any type-related checks.
10567 if (!IsThreeWay || IsAnyPointerType(LHS) || IsAnyPointerType(RHS)) {
10568 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
10569 if (LHS.isInvalid())
10570 return QualType();
10571 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
10572 if (RHS.isInvalid())
10573 return QualType();
10574 } else {
10575 LHS = DefaultLvalueConversion(LHS.get());
10576 if (LHS.isInvalid())
10577 return QualType();
10578 RHS = DefaultLvalueConversion(RHS.get());
10579 if (RHS.isInvalid())
10580 return QualType();
10581 }
10582
10583 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true);
10584
10585 // Handle vector comparisons separately.
10586 if (LHS.get()->getType()->isVectorType() ||
10587 RHS.get()->getType()->isVectorType())
10588 return CheckVectorCompareOperands(LHS, RHS, Loc, Opc);
10589
10590 diagnoseLogicalNotOnLHSofCheck(*this, LHS, RHS, Loc, Opc);
10591 diagnoseTautologicalComparison(*this, Loc, LHS.get(), RHS.get(), Opc);
10592
10593 QualType LHSType = LHS.get()->getType();
10594 QualType RHSType = RHS.get()->getType();
10595 if ((LHSType->isArithmeticType() || LHSType->isEnumeralType()) &&
10596 (RHSType->isArithmeticType() || RHSType->isEnumeralType()))
10597 return checkArithmeticOrEnumeralCompare(*this, LHS, RHS, Loc, Opc);
10598
10599 const Expr::NullPointerConstantKind LHSNullKind =
10600 LHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
10601 const Expr::NullPointerConstantKind RHSNullKind =
10602 RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
10603 bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
10604 bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
10605
10606 auto computeResultTy = [&]() {
10607 if (Opc != BO_Cmp)
10608 return Context.getLogicalOperationType();
10609 assert(getLangOpts().CPlusPlus);
10610 assert(Context.hasSameType(LHS.get()->getType(), RHS.get()->getType()));
10611
10612 QualType CompositeTy = LHS.get()->getType();
10613 assert(!CompositeTy->isReferenceType());
10614
10615 auto buildResultTy = [&](ComparisonCategoryType Kind) {
10616 return CheckComparisonCategoryType(Kind, Loc);
10617 };
10618
10619 // C++2a [expr.spaceship]p7: If the composite pointer type is a function
10620 // pointer type, a pointer-to-member type, or std::nullptr_t, the
10621 // result is of type std::strong_equality
10622 if (CompositeTy->isFunctionPointerType() ||
10623 CompositeTy->isMemberPointerType() || CompositeTy->isNullPtrType())
10624 // FIXME: consider making the function pointer case produce
10625 // strong_ordering not strong_equality, per P0946R0-Jax18 discussion
10626 // and direction polls
10627 return buildResultTy(ComparisonCategoryType::StrongEquality);
10628
10629 // C++2a [expr.spaceship]p8: If the composite pointer type is an object
10630 // pointer type, p <=> q is of type std::strong_ordering.
10631 if (CompositeTy->isPointerType()) {
10632 // P0946R0: Comparisons between a null pointer constant and an object
10633 // pointer result in std::strong_equality
10634 if (LHSIsNull != RHSIsNull)
10635 return buildResultTy(ComparisonCategoryType::StrongEquality);
10636 return buildResultTy(ComparisonCategoryType::StrongOrdering);
10637 }
10638 // C++2a [expr.spaceship]p9: Otherwise, the program is ill-formed.
10639 // TODO: Extend support for operator<=> to ObjC types.
10640 return InvalidOperands(Loc, LHS, RHS);
10641 };
10642
10643
10644 if (!IsRelational && LHSIsNull != RHSIsNull) {
10645 bool IsEquality = Opc == BO_EQ;
10646 if (RHSIsNull)
10647 DiagnoseAlwaysNonNullPointer(LHS.get(), RHSNullKind, IsEquality,
10648 RHS.get()->getSourceRange());
10649 else
10650 DiagnoseAlwaysNonNullPointer(RHS.get(), LHSNullKind, IsEquality,
10651 LHS.get()->getSourceRange());
10652 }
10653
10654 if ((LHSType->isIntegerType() && !LHSIsNull) ||
10655 (RHSType->isIntegerType() && !RHSIsNull)) {
10656 // Skip normal pointer conversion checks in this case; we have better
10657 // diagnostics for this below.
10658 } else if (getLangOpts().CPlusPlus) {
10659 // Equality comparison of a function pointer to a void pointer is invalid,
10660 // but we allow it as an extension.
10661 // FIXME: If we really want to allow this, should it be part of composite
10662 // pointer type computation so it works in conditionals too?
10663 if (!IsRelational &&
10664 ((LHSType->isFunctionPointerType() && RHSType->isVoidPointerType()) ||
10665 (RHSType->isFunctionPointerType() && LHSType->isVoidPointerType()))) {
10666 // This is a gcc extension compatibility comparison.
10667 // In a SFINAE context, we treat this as a hard error to maintain
10668 // conformance with the C++ standard.
10669 diagnoseFunctionPointerToVoidComparison(
10670 *this, Loc, LHS, RHS, /*isError*/ (bool)isSFINAEContext());
10671
10672 if (isSFINAEContext())
10673 return QualType();
10674
10675 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
10676 return computeResultTy();
10677 }
10678
10679 // C++ [expr.eq]p2:
10680 // If at least one operand is a pointer [...] bring them to their
10681 // composite pointer type.
10682 // C++ [expr.spaceship]p6
10683 // If at least one of the operands is of pointer type, [...] bring them
10684 // to their composite pointer type.
10685 // C++ [expr.rel]p2:
10686 // If both operands are pointers, [...] bring them to their composite
10687 // pointer type.
10688 if ((int)LHSType->isPointerType() + (int)RHSType->isPointerType() >=
10689 (IsRelational ? 2 : 1) &&
10690 (!LangOpts.ObjCAutoRefCount || !(LHSType->isObjCObjectPointerType() ||
10691 RHSType->isObjCObjectPointerType()))) {
10692 if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
10693 return QualType();
10694 return computeResultTy();
10695 }
10696 } else if (LHSType->isPointerType() &&
10697 RHSType->isPointerType()) { // C99 6.5.8p2
10698 bool LHSIsCap = LHSType->isCHERICapabilityType(Context);
10699 bool RHSIsCap = RHSType->isCHERICapabilityType(Context);
10700
10701 // Binary operations between pointers and capabilities are errors
10702 if (LHSIsCap != RHSIsCap && !(LHSIsNull || RHSIsNull))
10703 Diag(Loc, diag::err_typecheck_comparison_of_pointer_capability)
10704 << LHSType << RHSType << LHS.get()->getSourceRange()
10705 << RHS.get()->getSourceRange();
10706
10707 // We only implicitly cast the NULL constant to a memory capability
10708 if (LHSIsNull && !LHSIsCap && RHSIsCap)
10709 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_PointerToCHERICapability);
10710 else if (RHSIsNull && !RHSIsCap && LHSIsCap)
10711 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_PointerToCHERICapability);
10712
10713 // All of the following pointer-related warnings are GCC extensions, except
10714 // when handling null pointer constants.
10715 QualType LCanPointeeTy =
10716 LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
10717 QualType RCanPointeeTy =
10718 RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
10719
10720 // C99 6.5.9p2 and C99 6.5.8p2
10721 if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(),
10722 RCanPointeeTy.getUnqualifiedType())) {
10723 // Valid unless a relational comparison of function pointers
10724 if (IsRelational && LCanPointeeTy->isFunctionType()) {
10725 Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers)
10726 << LHSType << RHSType << LHS.get()->getSourceRange()
10727 << RHS.get()->getSourceRange();
10728 }
10729 } else if (!IsRelational &&
10730 (LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
10731 // Valid unless comparison between non-null pointer and function pointer
10732 if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
10733 && !LHSIsNull && !RHSIsNull)
10734 diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS,
10735 /*isError*/false);
10736 } else {
10737 // Invalid
10738 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false);
10739 }
10740 if (LCanPointeeTy != RCanPointeeTy) {
10741 // Treat NULL constant as a special case in OpenCL.
10742 if (getLangOpts().OpenCL && !LHSIsNull && !RHSIsNull) {
10743 const PointerType *LHSPtr = LHSType->getAs<PointerType>();
10744 if (!LHSPtr->isAddressSpaceOverlapping(*RHSType->getAs<PointerType>())) {
10745 Diag(Loc,
10746 diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
10747 << LHSType << RHSType << 0 /* comparison */
10748 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
10749 }
10750 }
10751 LangAS AddrSpaceL = LCanPointeeTy.getAddressSpace();
10752 LangAS AddrSpaceR = RCanPointeeTy.getAddressSpace();
10753 CastKind Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion
10754 : CK_BitCast;
10755 if (LHSIsNull && !RHSIsNull)
10756 LHS = ImpCastExprToType(LHS.get(), RHSType, Kind);
10757 else
10758 RHS = ImpCastExprToType(RHS.get(), LHSType, Kind);
10759 }
10760 return computeResultTy();
10761 }
10762
10763 if (getLangOpts().CPlusPlus) {
10764 // C++ [expr.eq]p4:
10765 // Two operands of type std::nullptr_t or one operand of type
10766 // std::nullptr_t and the other a null pointer constant compare equal.
10767 if (!IsRelational && LHSIsNull && RHSIsNull) {
10768 if (LHSType->isNullPtrType()) {
10769 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
10770 return computeResultTy();
10771 }
10772 if (RHSType->isNullPtrType()) {
10773 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
10774 return computeResultTy();
10775 }
10776 }
10777
10778 // Comparison of Objective-C pointers and block pointers against nullptr_t.
10779 // These aren't covered by the composite pointer type rules.
10780 if (!IsRelational && RHSType->isNullPtrType() &&
10781 (LHSType->isObjCObjectPointerType() || LHSType->isBlockPointerType())) {
10782 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
10783 return computeResultTy();
10784 }
10785 if (!IsRelational && LHSType->isNullPtrType() &&
10786 (RHSType->isObjCObjectPointerType() || RHSType->isBlockPointerType())) {
10787 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
10788 return computeResultTy();
10789 }
10790
10791 if (IsRelational &&
10792 ((LHSType->isNullPtrType() && RHSType->isPointerType()) ||
10793 (RHSType->isNullPtrType() && LHSType->isPointerType()))) {
10794 // HACK: Relational comparison of nullptr_t against a pointer type is
10795 // invalid per DR583, but we allow it within std::less<> and friends,
10796 // since otherwise common uses of it break.
10797 // FIXME: Consider removing this hack once LWG fixes std::less<> and
10798 // friends to have std::nullptr_t overload candidates.
10799 DeclContext *DC = CurContext;
10800 if (isa<FunctionDecl>(DC))
10801 DC = DC->getParent();
10802 if (auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(DC)) {
10803 if (CTSD->isInStdNamespace() &&
10804 llvm::StringSwitch<bool>(CTSD->getName())
10805 .Cases("less", "less_equal", "greater", "greater_equal", true)
10806 .Default(false)) {
10807 if (RHSType->isNullPtrType())
10808 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
10809 else
10810 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
10811 return computeResultTy();
10812 }
10813 }
10814 }
10815
10816 // C++ [expr.eq]p2:
10817 // If at least one operand is a pointer to member, [...] bring them to
10818 // their composite pointer type.
10819 if (!IsRelational &&
10820 (LHSType->isMemberPointerType() || RHSType->isMemberPointerType())) {
10821 if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
10822 return QualType();
10823 else
10824 return computeResultTy();
10825 }
10826 }
10827
10828 // Handle block pointer types.
10829 if (!IsRelational && LHSType->isBlockPointerType() &&
10830 RHSType->isBlockPointerType()) {
10831 QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType();
10832 QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType();
10833
10834 if (!LHSIsNull && !RHSIsNull &&
10835 !Context.typesAreCompatible(lpointee, rpointee)) {
10836 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
10837 << LHSType << RHSType << LHS.get()->getSourceRange()
10838 << RHS.get()->getSourceRange();
10839 }
10840 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
10841 return computeResultTy();
10842 }
10843
10844 // Allow block pointers to be compared with null pointer constants.
10845 if (!IsRelational
10846 && ((LHSType->isBlockPointerType() && RHSType->isPointerType())
10847 || (LHSType->isPointerType() && RHSType->isBlockPointerType()))) {
10848 if (!LHSIsNull && !RHSIsNull) {
10849 if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>()
10850 ->getPointeeType()->isVoidType())
10851 || (LHSType->isPointerType() && LHSType->castAs<PointerType>()
10852 ->getPointeeType()->isVoidType())))
10853 Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
10854 << LHSType << RHSType << LHS.get()->getSourceRange()
10855 << RHS.get()->getSourceRange();
10856 }
10857 if (LHSIsNull && !RHSIsNull)
10858 LHS = ImpCastExprToType(LHS.get(), RHSType,
10859 RHSType->isPointerType() ? CK_BitCast
10860 : CK_AnyPointerToBlockPointerCast);
10861 else
10862 RHS = ImpCastExprToType(RHS.get(), LHSType,
10863 LHSType->isPointerType() ? CK_BitCast
10864 : CK_AnyPointerToBlockPointerCast);
10865 return computeResultTy();
10866 }
10867
10868 if (LHSType->isObjCObjectPointerType() ||
10869 RHSType->isObjCObjectPointerType()) {
10870 const PointerType *LPT = LHSType->getAs<PointerType>();
10871 const PointerType *RPT = RHSType->getAs<PointerType>();
10872 if (LPT || RPT) {
10873 bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false;
10874 bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false;
10875
10876 if (!LPtrToVoid && !RPtrToVoid &&
10877 !Context.typesAreCompatible(LHSType, RHSType)) {
10878 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
10879 /*isError*/false);
10880 }
10881 if (LHSIsNull && !RHSIsNull) {
10882 Expr *E = LHS.get();
10883 if (getLangOpts().ObjCAutoRefCount)
10884 CheckObjCConversion(SourceRange(), RHSType, E,
10885 CCK_ImplicitConversion);
10886 LHS = ImpCastExprToType(E, RHSType,
10887 RPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
10888 }
10889 else {
10890 Expr *E = RHS.get();
10891 if (getLangOpts().ObjCAutoRefCount)
10892 CheckObjCConversion(SourceRange(), LHSType, E, CCK_ImplicitConversion,
10893 /*Diagnose=*/true,
10894 /*DiagnoseCFAudited=*/false, Opc);
10895 RHS = ImpCastExprToType(E, LHSType,
10896 LPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
10897 }
10898 return computeResultTy();
10899 }
10900 if (LHSType->isObjCObjectPointerType() &&
10901 RHSType->isObjCObjectPointerType()) {
10902 if (!Context.areComparableObjCPointerTypes(LHSType, RHSType))
10903 diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
10904 /*isError*/false);
10905 if (isObjCObjectLiteral(LHS) || isObjCObjectLiteral(RHS))
10906 diagnoseObjCLiteralComparison(*this, Loc, LHS, RHS, Opc);
10907
10908 if (LHSIsNull && !RHSIsNull)
10909 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
10910 else
10911 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
10912 return computeResultTy();
10913 }
10914
10915 if (!IsRelational && LHSType->isBlockPointerType() &&
10916 RHSType->isBlockCompatibleObjCPointerType(Context)) {
10917 LHS = ImpCastExprToType(LHS.get(), RHSType,
10918 CK_BlockPointerToObjCPointerCast);
10919 return computeResultTy();
10920 } else if (!IsRelational &&
10921 LHSType->isBlockCompatibleObjCPointerType(Context) &&
10922 RHSType->isBlockPointerType()) {
10923 RHS = ImpCastExprToType(RHS.get(), LHSType,
10924 CK_BlockPointerToObjCPointerCast);
10925 return computeResultTy();
10926 }
10927 }
10928 if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) ||
10929 (LHSType->isIntegerType() && RHSType->isAnyPointerType())) {
10930 unsigned DiagID = 0;
10931 bool isError = false;
10932 if (LangOpts.DebuggerSupport) {
10933 // Under a debugger, allow the comparison of pointers to integers,
10934 // since users tend to want to compare addresses.
10935 } else if ((LHSIsNull && LHSType->isIntegerType()) ||
10936 (RHSIsNull && RHSType->isIntegerType())) {
10937 if (IsRelational) {
10938 isError = getLangOpts().CPlusPlus;
10939 DiagID =
10940 isError ? diag::err_typecheck_ordered_comparison_of_pointer_and_zero
10941 : diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
10942 }
10943 } else if (getLangOpts().CPlusPlus) {
10944 DiagID = diag::err_typecheck_comparison_of_pointer_integer;
10945 isError = true;
10946 } else if (IsRelational)
10947 DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
10948 else
10949 DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
10950
10951 if (DiagID) {
10952 Diag(Loc, DiagID)
10953 << LHSType << RHSType << LHS.get()->getSourceRange()
10954 << RHS.get()->getSourceRange();
10955 if (isError)
10956 return QualType();
10957 }
10958
10959 if (LHSType->isIntegerType())
10960 LHS = ImpCastExprToType(LHS.get(), RHSType,
10961 LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
10962 else
10963 RHS = ImpCastExprToType(RHS.get(), LHSType,
10964 RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
10965 return computeResultTy();
10966 }
10967
10968 // Handle block pointers.
10969 if (!IsRelational && RHSIsNull
10970 && LHSType->isBlockPointerType() && RHSType->isIntegerType()) {
10971 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
10972 return computeResultTy();
10973 }
10974 if (!IsRelational && LHSIsNull
10975 && LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
10976 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
10977 return computeResultTy();
10978 }
10979
10980 if (getLangOpts().OpenCLVersion >= 200 || getLangOpts().OpenCLCPlusPlus) {
10981 if (LHSType->isClkEventT() && RHSType->isClkEventT()) {
10982 return computeResultTy();
10983 }
10984
10985 if (LHSType->isQueueT() && RHSType->isQueueT()) {
10986 return computeResultTy();
10987 }
10988
10989 if (LHSIsNull && RHSType->isQueueT()) {
10990 LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
10991 return computeResultTy();
10992 }
10993
10994 if (LHSType->isQueueT() && RHSIsNull) {
10995 RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
10996 return computeResultTy();
10997 }
10998 }
10999
11000 return InvalidOperands(Loc, LHS, RHS);
11001}
11002
11003// Return a signed ext_vector_type that is of identical size and number of
11004// elements. For floating point vectors, return an integer type of identical
11005// size and number of elements. In the non ext_vector_type case, search from
11006// the largest type to the smallest type to avoid cases where long long == long,
11007// where long gets picked over long long.
11008QualType Sema::GetSignedVectorType(QualType V) {
11009 const VectorType *VTy = V->getAs<VectorType>();
11010 unsigned TypeSize = Context.getTypeSize(VTy->getElementType());
11011
11012 if (isa<ExtVectorType>(VTy)) {
11013 if (TypeSize == Context.getTypeSize(Context.CharTy))
11014 return Context.getExtVectorType(Context.CharTy, VTy->getNumElements());
11015 else if (TypeSize == Context.getTypeSize(Context.ShortTy))
11016 return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements());
11017 else if (TypeSize == Context.getTypeSize(Context.IntTy))
11018 return Context.getExtVectorType(Context.IntTy, VTy->getNumElements());
11019 else if (TypeSize == Context.getTypeSize(Context.LongTy))
11020 return Context.getExtVectorType(Context.LongTy, VTy->getNumElements());
11021 assert(TypeSize == Context.getTypeSize(Context.LongLongTy) &&
11022 "Unhandled vector element size in vector compare");
11023 return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements());
11024 }
11025
11026 if (TypeSize == Context.getTypeSize(Context.LongLongTy))
11027 return Context.getVectorType(Context.LongLongTy, VTy->getNumElements(),
11028 VectorType::GenericVector);
11029 else if (TypeSize == Context.getTypeSize(Context.LongTy))
11030 return Context.getVectorType(Context.LongTy, VTy->getNumElements(),
11031 VectorType::GenericVector);
11032 else if (TypeSize == Context.getTypeSize(Context.IntTy))
11033 return Context.getVectorType(Context.IntTy, VTy->getNumElements(),
11034 VectorType::GenericVector);
11035 else if (TypeSize == Context.getTypeSize(Context.ShortTy))
11036 return Context.getVectorType(Context.ShortTy, VTy->getNumElements(),
11037 VectorType::GenericVector);
11038 assert(TypeSize == Context.getTypeSize(Context.CharTy) &&
11039 "Unhandled vector element size in vector compare");
11040 return Context.getVectorType(Context.CharTy, VTy->getNumElements(),
11041 VectorType::GenericVector);
11042}
11043
11044/// CheckVectorCompareOperands - vector comparisons are a clang extension that
11045/// operates on extended vector types. Instead of producing an IntTy result,
11046/// like a scalar comparison, a vector comparison produces a vector of integer
11047/// types.
11048QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
11049 SourceLocation Loc,
11050 BinaryOperatorKind Opc) {
11051 // Check to make sure we're operating on vectors of the same type and width,
11052 // Allowing one side to be a scalar of element type.
11053 QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false,
11054 /*AllowBothBool*/true,
11055 /*AllowBoolConversions*/getLangOpts().ZVector);
11056 if (vType.isNull())
11057 return vType;
11058
11059 QualType LHSType = LHS.get()->getType();
11060
11061 // If AltiVec, the comparison results in a numeric type, i.e.
11062 // bool for C++, int for C
11063 if (getLangOpts().AltiVec &&
11064 vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector)
11065 return Context.getLogicalOperationType();
11066
11067 // For non-floating point types, check for self-comparisons of the form
11068 // x == x, x != x, x < x, etc. These always evaluate to a constant, and
11069 // often indicate logic errors in the program.
11070 diagnoseTautologicalComparison(*this, Loc, LHS.get(), RHS.get(), Opc);
11071
11072 // Check for comparisons of floating point operands using != and ==.
11073 if (BinaryOperator::isEqualityOp(Opc) &&
11074 LHSType->hasFloatingRepresentation()) {
11075 assert(RHS.get()->getType()->hasFloatingRepresentation());
11076 CheckFloatComparison(Loc, LHS.get(), RHS.get());
11077 }
11078
11079 // Return a signed type for the vector.
11080 return GetSignedVectorType(vType);
11081}
11082
11083QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
11084 SourceLocation Loc) {
11085 // Ensure that either both operands are of the same vector type, or
11086 // one operand is of a vector type and the other is of its element type.
11087 QualType vType = CheckVectorOperands(LHS, RHS, Loc, false,
11088 /*AllowBothBool*/true,
11089 /*AllowBoolConversions*/false);
11090 if (vType.isNull())
11091 return InvalidOperands(Loc, LHS, RHS);
11092 if (getLangOpts().OpenCL && getLangOpts().OpenCLVersion < 120 &&
11093 !getLangOpts().OpenCLCPlusPlus && vType->hasFloatingRepresentation())
11094 return InvalidOperands(Loc, LHS, RHS);
11095 // FIXME: The check for C++ here is for GCC compatibility. GCC rejects the
11096 // usage of the logical operators && and || with vectors in C. This
11097 // check could be notionally dropped.
11098 if (!getLangOpts().CPlusPlus &&
11099 !(isa<ExtVectorType>(vType->getAs<VectorType>())))
11100 return InvalidLogicalVectorOperands(Loc, LHS, RHS);
11101
11102 return GetSignedVectorType(LHS.get()->getType());
11103}
11104
11105inline QualType Sema::CheckBitwiseOperands(ExprResult &LHS, ExprResult &RHS,
11106 SourceLocation Loc,
11107 BinaryOperatorKind Opc) {
11108 checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
11109
11110 // For the CHERI checks below we want to look at the unpromoted type
11111 QualType OriginalLHSType = LHS.get()->getType();
11112
11113 bool IsCompAssign =
11114 Opc == BO_AndAssign || Opc == BO_OrAssign || Opc == BO_XorAssign;
11115
11116 if (LHS.get()->getType()->isVectorType() ||
11117 RHS.get()->getType()->isVectorType()) {
11118 if (LHS.get()->getType()->hasIntegerRepresentation() &&
11119 RHS.get()->getType()->hasIntegerRepresentation())
11120 return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
11121 /*AllowBothBool*/true,
11122 /*AllowBoolConversions*/getLangOpts().ZVector);
11123 return InvalidOperands(Loc, LHS, RHS);
11124 }
11125
11126 if (Opc == BO_And)
11127 diagnoseLogicalNotOnLHSofCheck(*this, LHS, RHS, Loc, Opc);
11128
11129 ExprResult LHSResult = LHS, RHSResult = RHS;
11130 QualType compType = UsualArithmeticConversions(LHSResult, RHSResult,
11131 IsCompAssign);
11132 if (LHSResult.isInvalid() || RHSResult.isInvalid())
11133 return QualType();
11134 LHS = LHSResult.get();
11135 RHS = RHSResult.get();
11136
11137 if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType()) {
11138 bool isLHSCap = OriginalLHSType->isCHERICapabilityType(Context);
11139 bool isRHSCap = RHS.get()->getType()->isCHERICapabilityType(Context);
11140 bool UsingUIntCapOffset = getLangOpts().cheriUIntCapUsesOffset();
11141 if (isLHSCap && (Opc == BO_And || Opc == BO_AndAssign)) {
11142 // Bitwise and can cause checking low pointer bits to be compiled to
11143 // and always false condition (see CTSRD-CHERI/clang#189) unless we
11144 // have CheriDataDependentProvenance enabled. It also gives surprising
11145 // behaviour if we are compiling in uintcap=offset mode so warn if either
11146 // of these conditions are met:
11147 if (UsingUIntCapOffset || !getLangOpts().CheriDataDependentProvenance)
11148 DiagRuntimeBehavior(Loc, RHS.get(),
11149 PDiag(diag::warn_uintcap_bitwise_and)
11150 << LHS.get()->getSourceRange()
11151 << RHS.get()->getSourceRange());
11152 } else if (UsingUIntCapOffset && isLHSCap &&
11153 (Opc == BO_Xor || Opc == BO_XorAssign)) {
11154 // XOR is highly dubious when in offset mode (except when using on plain
11155 // integer values, but then the user should be using size_t/vaddr_t and
11156 // not uintcap_t. Don't warn in address mode since that works just fine
11157 // (only slightly less efficiently)
11158 DiagRuntimeBehavior(Loc, RHS.get(),
11159 PDiag(diag::warn_uintcap_bad_bitwise_op)
11160 << 0 /*=xor*/ << 0 /* usecase is hashing */
11161 << LHS.get()->getSourceRange()
11162 << RHS.get()->getSourceRange());
11163 } else if ((isLHSCap && !isRHSCap) || (!isLHSCap && isRHSCap)) {
11164 // FIXME: this warning is not always useful
11165 DiagRuntimeBehavior(Loc, RHS.get(),
11166 PDiag(diag::warn_mixed_capability_binop)
11167 << OriginalLHSType << RHS.get()->getType()
11168 << LHS.get()->getSourceRange()
11169 << RHS.get()->getSourceRange());
11170 }
11171 return compType;
11172 }
11173 return InvalidOperands(Loc, LHS, RHS);
11174}
11175
11176// C99 6.5.[13,14]
11177inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
11178 SourceLocation Loc,
11179 BinaryOperatorKind Opc) {
11180 // Check vector operands differently.
11181 if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType())
11182 return CheckVectorLogicalOperands(LHS, RHS, Loc);
11183
11184 // Diagnose cases where the user write a logical and/or but probably meant a
11185 // bitwise one. We do this when the LHS is a non-bool integer and the RHS
11186 // is a constant.
11187 if (LHS.get()->getType()->isIntegerType() &&
11188 !LHS.get()->getType()->isBooleanType() &&
11189 RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
11190 // Don't warn in macros or template instantiations.
11191 !Loc.isMacroID() && !inTemplateInstantiation()) {
11192 // If the RHS can be constant folded, and if it constant folds to something
11193 // that isn't 0 or 1 (which indicate a potential logical operation that
11194 // happened to fold to true/false) then warn.
11195 // Parens on the RHS are ignored.
11196 Expr::EvalResult EVResult;
11197 if (RHS.get()->EvaluateAsInt(EVResult, Context)) {
11198 llvm::APSInt Result = EVResult.Val.getInt();
11199 if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType() &&
11200 !RHS.get()->getExprLoc().isMacroID()) ||
11201 (Result != 0 && Result != 1)) {
11202 Diag(Loc, diag::warn_logical_instead_of_bitwise)
11203 << RHS.get()->getSourceRange()
11204 << (Opc == BO_LAnd ? "&&" : "||");
11205 // Suggest replacing the logical operator with the bitwise version
11206 Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator)
11207 << (Opc == BO_LAnd ? "&" : "|")
11208 << FixItHint::CreateReplacement(SourceRange(
11209 Loc, getLocForEndOfToken(Loc)),
11210 Opc == BO_LAnd ? "&" : "|");
11211 if (Opc == BO_LAnd)
11212 // Suggest replacing "Foo() && kNonZero" with "Foo()"
11213 Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant)
11214 << FixItHint::CreateRemoval(
11215 SourceRange(getLocForEndOfToken(LHS.get()->getEndLoc()),
11216 RHS.get()->getEndLoc()));
11217 }
11218 }
11219 }
11220
11221 if (!Context.getLangOpts().CPlusPlus) {
11222 // OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do
11223 // not operate on the built-in scalar and vector float types.
11224 if (Context.getLangOpts().OpenCL &&
11225 Context.getLangOpts().OpenCLVersion < 120) {
11226 if (LHS.get()->getType()->isFloatingType() ||
11227 RHS.get()->getType()->isFloatingType())
11228 return InvalidOperands(Loc, LHS, RHS);
11229 }
11230
11231 LHS = UsualUnaryConversions(LHS.get());
11232 if (LHS.isInvalid())
11233 return QualType();
11234
11235 RHS = UsualUnaryConversions(RHS.get());
11236 if (RHS.isInvalid())
11237 return QualType();
11238
11239 if (!LHS.get()->getType()->isScalarType() ||
11240 !RHS.get()->getType()->isScalarType())
11241 return InvalidOperands(Loc, LHS, RHS);
11242
11243 return Context.IntTy;
11244 }
11245
11246 // The following is safe because we only use this method for
11247 // non-overloadable operands.
11248
11249 // C++ [expr.log.and]p1
11250 // C++ [expr.log.or]p1
11251 // The operands are both contextually converted to type bool.
11252 ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get());
11253 if (LHSRes.isInvalid())
11254 return InvalidOperands(Loc, LHS, RHS);
11255 LHS = LHSRes;
11256
11257 ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get());
11258 if (RHSRes.isInvalid())
11259 return InvalidOperands(Loc, LHS, RHS);
11260 RHS = RHSRes;
11261
11262 // C++ [expr.log.and]p2
11263 // C++ [expr.log.or]p2
11264 // The result is a bool.
11265 return Context.BoolTy;
11266}
11267
11268static bool IsReadonlyMessage(Expr *E, Sema &S) {
11269 const MemberExpr *ME = dyn_cast<MemberExpr>(E);
11270 if (!ME) return false;
11271 if (!isa<FieldDecl>(ME->getMemberDecl())) return false;
11272 ObjCMessageExpr *Base = dyn_cast<ObjCMessageExpr>(
11273 ME->getBase()->IgnoreImplicit()->IgnoreParenImpCasts());
11274 if (!Base) return false;
11275 return Base->getMethodDecl() != nullptr;
11276}
11277
11278/// Is the given expression (which must be 'const') a reference to a
11279/// variable which was originally non-const, but which has become
11280/// 'const' due to being captured within a block?
11281enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda };
11282static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) {
11283 assert(E->isLValue() && E->getType().isConstQualified());
11284 E = E->IgnoreParens();
11285
11286 // Must be a reference to a declaration from an enclosing scope.
11287 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
11288 if (!DRE) return NCCK_None;
11289 if (!DRE->refersToEnclosingVariableOrCapture()) return NCCK_None;
11290
11291 // The declaration must be a variable which is not declared 'const'.
11292 VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl());
11293 if (!var) return NCCK_None;
11294 if (var->getType().isConstQualified()) return NCCK_None;
11295 assert(var->hasLocalStorage() && "capture added 'const' to non-local?");
11296
11297 // Decide whether the first capture was for a block or a lambda.
11298 DeclContext *DC = S.CurContext, *Prev = nullptr;
11299 // Decide whether the first capture was for a block or a lambda.
11300 while (DC) {
11301 // For init-capture, it is possible that the variable belongs to the
11302 // template pattern of the current context.
11303 if (auto *FD = dyn_cast<FunctionDecl>(DC))
11304 if (var->isInitCapture() &&
11305 FD->getTemplateInstantiationPattern() == var->getDeclContext())
11306 break;
11307 if (DC == var->getDeclContext())
11308 break;
11309 Prev = DC;
11310 DC = DC->getParent();
11311 }
11312 // Unless we have an init-capture, we've gone one step too far.
11313 if (!var->isInitCapture())
11314 DC = Prev;
11315 return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda);
11316}
11317
11318static bool IsTypeModifiable(QualType Ty, bool IsDereference) {
11319 Ty = Ty.getNonReferenceType();
11320 if (IsDereference && Ty->isPointerType())
11321 Ty = Ty->getPointeeType();
11322 return !Ty.isConstQualified();
11323}
11324
11325// Update err_typecheck_assign_const and note_typecheck_assign_const
11326// when this enum is changed.
11327enum {
11328 ConstFunction,
11329 ConstVariable,
11330 ConstMember,
11331 ConstMethod,
11332 NestedConstMember,
11333 ConstUnknown, // Keep as last element
11334};
11335
11336/// Emit the "read-only variable not assignable" error and print notes to give
11337/// more information about why the variable is not assignable, such as pointing
11338/// to the declaration of a const variable, showing that a method is const, or
11339/// that the function is returning a const reference.
11340static void DiagnoseConstAssignment(Sema &S, const Expr *E,
11341 SourceLocation Loc) {
11342 SourceRange ExprRange = E->getSourceRange();
11343
11344 // Only emit one error on the first const found. All other consts will emit
11345 // a note to the error.
11346 bool DiagnosticEmitted = false;
11347
11348 // Track if the current expression is the result of a dereference, and if the
11349 // next checked expression is the result of a dereference.
11350 bool IsDereference = false;
11351 bool NextIsDereference = false;
11352
11353 // Loop to process MemberExpr chains.
11354 while (true) {
11355 IsDereference = NextIsDereference;
11356
11357 E = E->IgnoreImplicit()->IgnoreParenImpCasts();
11358 if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
11359 NextIsDereference = ME->isArrow();
11360 const ValueDecl *VD = ME->getMemberDecl();
11361 if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
11362 // Mutable fields can be modified even if the class is const.
11363 if (Field->isMutable()) {
11364 assert(DiagnosticEmitted && "Expected diagnostic not emitted.");
11365 break;
11366 }
11367
11368 if (!IsTypeModifiable(Field->getType(), IsDereference)) {
11369 if (!DiagnosticEmitted) {
11370 S.Diag(Loc, diag::err_typecheck_assign_const)
11371 << ExprRange << ConstMember << false /*static*/ << Field
11372 << Field->getType();
11373 DiagnosticEmitted = true;
11374 }
11375 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
11376 << ConstMember << false /*static*/ << Field << Field->getType()
11377 << Field->getSourceRange();
11378 }
11379 E = ME->getBase();
11380 continue;
11381 } else if (const VarDecl *VDecl = dyn_cast<VarDecl>(VD)) {
11382 if (VDecl->getType().isConstQualified()) {
11383 if (!DiagnosticEmitted) {
11384 S.Diag(Loc, diag::err_typecheck_assign_const)
11385 << ExprRange << ConstMember << true /*static*/ << VDecl
11386 << VDecl->getType();
11387 DiagnosticEmitted = true;
11388 }
11389 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
11390 << ConstMember << true /*static*/ << VDecl << VDecl->getType()
11391 << VDecl->getSourceRange();
11392 }
11393 // Static fields do not inherit constness from parents.
11394 break;
11395 }
11396 break; // End MemberExpr
11397 } else if (const ArraySubscriptExpr *ASE =
11398 dyn_cast<ArraySubscriptExpr>(E)) {
11399 E = ASE->getBase()->IgnoreParenImpCasts();
11400 continue;
11401 } else if (const ExtVectorElementExpr *EVE =
11402 dyn_cast<ExtVectorElementExpr>(E)) {
11403 E = EVE->getBase()->IgnoreParenImpCasts();
11404 continue;
11405 }
11406 break;
11407 }
11408
11409 if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
11410 // Function calls
11411 const FunctionDecl *FD = CE->getDirectCallee();
11412 if (FD && !IsTypeModifiable(FD->getReturnType(), IsDereference)) {
11413 if (!DiagnosticEmitted) {
11414 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
11415 << ConstFunction << FD;
11416 DiagnosticEmitted = true;
11417 }
11418 S.Diag(FD->getReturnTypeSourceRange().getBegin(),
11419 diag::note_typecheck_assign_const)
11420 << ConstFunction << FD << FD->getReturnType()
11421 << FD->getReturnTypeSourceRange();
11422 }
11423 } else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
11424 // Point to variable declaration.
11425 if (const ValueDecl *VD = DRE->getDecl()) {
11426 if (!IsTypeModifiable(VD->getType(), IsDereference)) {
11427 if (!DiagnosticEmitted) {
11428 S.Diag(Loc, diag::err_typecheck_assign_const)
11429 << ExprRange << ConstVariable << VD << VD->getType();
11430 DiagnosticEmitted = true;
11431 }
11432 S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
11433 << ConstVariable << VD << VD->getType() << VD->getSourceRange();
11434 }
11435 }
11436 } else if (isa<CXXThisExpr>(E)) {
11437 if (const DeclContext *DC = S.getFunctionLevelDeclContext()) {
11438 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) {
11439 if (MD->isConst()) {
11440 if (!DiagnosticEmitted) {
11441 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
11442 << ConstMethod << MD;
11443 DiagnosticEmitted = true;
11444 }
11445 S.Diag(MD->getLocation(), diag::note_typecheck_assign_const)
11446 << ConstMethod << MD << MD->getSourceRange();
11447 }
11448 }
11449 }
11450 }
11451
11452 if (DiagnosticEmitted)
11453 return;
11454
11455 // Can't determine a more specific message, so display the generic error.
11456 S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange << ConstUnknown;
11457}
11458
11459enum OriginalExprKind {
11460 OEK_Variable,
11461 OEK_Member,
11462 OEK_LValue
11463};
11464
11465static void DiagnoseRecursiveConstFields(Sema &S, const ValueDecl *VD,
11466 const RecordType *Ty,
11467 SourceLocation Loc, SourceRange Range,
11468 OriginalExprKind OEK,
11469 bool &DiagnosticEmitted) {
11470 std::vector<const RecordType *> RecordTypeList;
11471 RecordTypeList.push_back(Ty);
11472 unsigned NextToCheckIndex = 0;
11473 // We walk the record hierarchy breadth-first to ensure that we print
11474 // diagnostics in field nesting order.
11475 while (RecordTypeList.size() > NextToCheckIndex) {
11476 bool IsNested = NextToCheckIndex > 0;
11477 for (const FieldDecl *Field :
11478 RecordTypeList[NextToCheckIndex]->getDecl()->fields()) {
11479 // First, check every field for constness.
11480 QualType FieldTy = Field->getType();
11481 if (FieldTy.isConstQualified()) {
11482 if (!DiagnosticEmitted) {
11483 S.Diag(Loc, diag::err_typecheck_assign_const)
11484 << Range << NestedConstMember << OEK << VD
11485 << IsNested << Field;
11486 DiagnosticEmitted = true;
11487 }
11488 S.Diag(Field->getLocation(), diag::note_typecheck_assign_const)
11489 << NestedConstMember << IsNested << Field
11490 << FieldTy << Field->getSourceRange();
11491 }
11492
11493 // Then we append it to the list to check next in order.
11494 FieldTy = FieldTy.getCanonicalType();
11495 if (const auto *FieldRecTy = FieldTy->getAs<RecordType>()) {
11496 if (llvm::find(RecordTypeList, FieldRecTy) == RecordTypeList.end())
11497 RecordTypeList.push_back(FieldRecTy);
11498 }
11499 }
11500 ++NextToCheckIndex;
11501 }
11502}
11503
11504/// Emit an error for the case where a record we are trying to assign to has a
11505/// const-qualified field somewhere in its hierarchy.
11506static void DiagnoseRecursiveConstFields(Sema &S, const Expr *E,
11507 SourceLocation Loc) {
11508 QualType Ty = E->getType();
11509 assert(Ty->isRecordType() && "lvalue was not record?");
11510 SourceRange Range = E->getSourceRange();
11511 const RecordType *RTy = Ty.getCanonicalType()->getAs<RecordType>();
11512 bool DiagEmitted = false;
11513
11514 if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
11515 DiagnoseRecursiveConstFields(S, ME->getMemberDecl(), RTy, Loc,
11516 Range, OEK_Member, DiagEmitted);
11517 else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
11518 DiagnoseRecursiveConstFields(S, DRE->getDecl(), RTy, Loc,
11519 Range, OEK_Variable, DiagEmitted);
11520 else
11521 DiagnoseRecursiveConstFields(S, nullptr, RTy, Loc,
11522 Range, OEK_LValue, DiagEmitted);
11523 if (!DiagEmitted)
11524 DiagnoseConstAssignment(S, E, Loc);
11525}
11526
11527/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not,
11528/// emit an error and return true. If so, return false.
11529static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) {
11530 assert(!E->hasPlaceholderType(BuiltinType::PseudoObject));
11531
11532 S.CheckShadowingDeclModification(E, Loc);
11533
11534 SourceLocation OrigLoc = Loc;
11535 Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context,
11536 &Loc);
11537 if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S))
11538 IsLV = Expr::MLV_InvalidMessageExpression;
11539 if (IsLV == Expr::MLV_Valid)
11540 return false;
11541
11542 unsigned DiagID = 0;
11543 bool NeedType = false;
11544 switch (IsLV) { // C99 6.5.16p2
11545 case Expr::MLV_ConstQualified:
11546 // Use a specialized diagnostic when we're assigning to an object
11547 // from an enclosing function or block.
11548 if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) {
11549 if (NCCK == NCCK_Block)
11550 DiagID = diag::err_block_decl_ref_not_modifiable_lvalue;
11551 else
11552 DiagID = diag::err_lambda_decl_ref_not_modifiable_lvalue;
11553 break;
11554 }
11555
11556 // In ARC, use some specialized diagnostics for occasions where we
11557 // infer 'const'. These are always pseudo-strong variables.
11558 if (S.getLangOpts().ObjCAutoRefCount) {
11559 DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts());
11560 if (declRef && isa<VarDecl>(declRef->getDecl())) {
11561 VarDecl *var = cast<VarDecl>(declRef->getDecl());
11562
11563 // Use the normal diagnostic if it's pseudo-__strong but the
11564 // user actually wrote 'const'.
11565 if (var->isARCPseudoStrong() &&
11566 (!var->getTypeSourceInfo() ||
11567 !var->getTypeSourceInfo()->getType().isConstQualified())) {
11568 // There are three pseudo-strong cases:
11569 // - self
11570 ObjCMethodDecl *method = S.getCurMethodDecl();
11571 if (method && var == method->getSelfDecl()) {
11572 DiagID = method->isClassMethod()
11573 ? diag::err_typecheck_arc_assign_self_class_method
11574 : diag::err_typecheck_arc_assign_self;
11575
11576 // - Objective-C externally_retained attribute.
11577 } else if (var->hasAttr<ObjCExternallyRetainedAttr>() ||
11578 isa<ParmVarDecl>(var)) {
11579 DiagID = diag::err_typecheck_arc_assign_externally_retained;
11580
11581 // - fast enumeration variables
11582 } else {
11583 DiagID = diag::err_typecheck_arr_assign_enumeration;
11584 }
11585
11586 SourceRange Assign;
11587 if (Loc != OrigLoc)
11588 Assign = SourceRange(OrigLoc, OrigLoc);
11589 S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
11590 // We need to preserve the AST regardless, so migration tool
11591 // can do its job.
11592 return false;
11593 }
11594 }
11595 }
11596
11597 // If none of the special cases above are triggered, then this is a
11598 // simple const assignment.
11599 if (DiagID == 0) {
11600 DiagnoseConstAssignment(S, E, Loc);
11601 return true;
11602 }
11603
11604 break;
11605 case Expr::MLV_ConstAddrSpace:
11606 DiagnoseConstAssignment(S, E, Loc);
11607 return true;
11608 case Expr::MLV_ConstQualifiedField:
11609 DiagnoseRecursiveConstFields(S, E, Loc);
11610 return true;
11611 case Expr::MLV_ArrayType:
11612 case Expr::MLV_ArrayTemporary:
11613 DiagID = diag::err_typecheck_array_not_modifiable_lvalue;
11614 NeedType = true;
11615 break;
11616 case Expr::MLV_NotObjectType:
11617 DiagID = diag::err_typecheck_non_object_not_modifiable_lvalue;
11618 NeedType = true;
11619 break;
11620 case Expr::MLV_LValueCast:
11621 DiagID = diag::err_typecheck_lvalue_casts_not_supported;
11622 break;
11623 case Expr::MLV_Valid:
11624 llvm_unreachable("did not take early return for MLV_Valid");
11625 case Expr::MLV_InvalidExpression:
11626 case Expr::MLV_MemberFunction:
11627 case Expr::MLV_ClassTemporary:
11628 DiagID = diag::err_typecheck_expression_not_modifiable_lvalue;
11629 break;
11630 case Expr::MLV_IncompleteType:
11631 case Expr::MLV_IncompleteVoidType:
11632 return S.RequireCompleteType(Loc, E->getType(),
11633 diag::err_typecheck_incomplete_type_not_modifiable_lvalue, E);
11634 case Expr::MLV_DuplicateVectorComponents:
11635 DiagID = diag::err_typecheck_duplicate_vector_components_not_mlvalue;
11636 break;
11637 case Expr::MLV_NoSetterProperty:
11638 llvm_unreachable("readonly properties should be processed differently");
11639 case Expr::MLV_InvalidMessageExpression:
11640 DiagID = diag::err_readonly_message_assignment;
11641 break;
11642 case Expr::MLV_SubObjCPropertySetting:
11643 DiagID = diag::err_no_subobject_property_setting;
11644 break;
11645 }
11646
11647 SourceRange Assign;
11648 if (Loc != OrigLoc)
11649 Assign = SourceRange(OrigLoc, OrigLoc);
11650 if (NeedType)
11651 S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign;
11652 else
11653 S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
11654 return true;
11655}
11656
11657static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr,
11658 SourceLocation Loc,
11659 Sema &Sema) {
11660 if (Sema.inTemplateInstantiation())
11661 return;
11662 if (Sema.isUnevaluatedContext())
11663 return;
11664 if (Loc.isInvalid() || Loc.isMacroID())
11665 return;
11666 if (LHSExpr->getExprLoc().isMacroID() || RHSExpr->getExprLoc().isMacroID())
11667 return;
11668
11669 // C / C++ fields
11670 MemberExpr *ML = dyn_cast<MemberExpr>(LHSExpr);
11671 MemberExpr *MR = dyn_cast<MemberExpr>(RHSExpr);
11672 if (ML && MR) {
11673 if (!(isa<CXXThisExpr>(ML->getBase()) && isa<CXXThisExpr>(MR->getBase())))
11674 return;
11675 const ValueDecl *LHSDecl =
11676 cast<ValueDecl>(ML->getMemberDecl()->getCanonicalDecl());
11677 const ValueDecl *RHSDecl =
11678 cast<ValueDecl>(MR->getMemberDecl()->getCanonicalDecl());
11679 if (LHSDecl != RHSDecl)
11680 return;
11681 if (LHSDecl->getType().isVolatileQualified())
11682 return;
11683 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
11684 if (RefTy->getPointeeType().isVolatileQualified())
11685 return;
11686
11687 Sema.Diag(Loc, diag::warn_identity_field_assign) << 0;
11688 }
11689
11690 // Objective-C instance variables
11691 ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(LHSExpr);
11692 ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(RHSExpr);
11693 if (OL && OR && OL->getDecl() == OR->getDecl()) {
11694 DeclRefExpr *RL = dyn_cast<DeclRefExpr>(OL->getBase()->IgnoreImpCasts());
11695 DeclRefExpr *RR = dyn_cast<DeclRefExpr>(OR->getBase()->IgnoreImpCasts());
11696 if (RL && RR && RL->getDecl() == RR->getDecl())
11697 Sema.Diag(Loc, diag::warn_identity_field_assign) << 1;
11698 }
11699}
11700
11701// C99 6.5.16.1
11702QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS,
11703 SourceLocation Loc,
11704 QualType CompoundType) {
11705 assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject));
11706
11707 // Verify that LHS is a modifiable lvalue, and emit error if not.
11708 if (CheckForModifiableLvalue(LHSExpr, Loc, *this))
11709 return QualType();
11710
11711 QualType LHSType = LHSExpr->getType();
11712 QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() :
11713 CompoundType;
11714 // OpenCL v1.2 s6.1.1.1 p2:
11715 // The half data type can only be used to declare a pointer to a buffer that
11716 // contains half values
11717 if (getLangOpts().OpenCL && !getOpenCLOptions().isEnabled("cl_khr_fp16") &&
11718 LHSType->isHalfType()) {
11719 Diag(Loc, diag::err_opencl_half_load_store) << 1
11720 << LHSType.getUnqualifiedType();
11721 return QualType();
11722 }
11723
11724 AssignConvertType ConvTy;
11725 if (CompoundType.isNull()) {
11726 Expr *RHSCheck = RHS.get();
11727
11728 CheckIdentityFieldAssignment(LHSExpr, RHSCheck, Loc, *this);
11729
11730 QualType LHSTy(LHSType);
11731 ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS);
11732 if (RHS.isInvalid())
11733 return QualType();
11734 // Special case of NSObject attributes on c-style pointer types.
11735 if (ConvTy == IncompatiblePointer &&
11736 ((Context.isObjCNSObjectType(LHSType) &&
11737 RHSType->isObjCObjectPointerType()) ||
11738 (Context.isObjCNSObjectType(RHSType) &&
11739 LHSType->isObjCObjectPointerType())))
11740 ConvTy = Compatible;
11741
11742 if (ConvTy == Compatible &&
11743 LHSType->isObjCObjectType())
11744 Diag(Loc, diag::err_objc_object_assignment)
11745 << LHSType;
11746
11747 // If the RHS is a unary plus or minus, check to see if they = and + are
11748 // right next to each other. If so, the user may have typo'd "x =+ 4"
11749 // instead of "x += 4".
11750 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck))
11751 RHSCheck = ICE->getSubExpr();
11752 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) {
11753 if ((UO->getOpcode() == UO_Plus || UO->getOpcode() == UO_Minus) &&
11754 Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
11755 // Only if the two operators are exactly adjacent.
11756 Loc.getLocWithOffset(1) == UO->getOperatorLoc() &&
11757 // And there is a space or other character before the subexpr of the
11758 // unary +/-. We don't want to warn on "x=-1".
11759 Loc.getLocWithOffset(2) != UO->getSubExpr()->getBeginLoc() &&
11760 UO->getSubExpr()->getBeginLoc().isFileID()) {
11761 Diag(Loc, diag::warn_not_compound_assign)
11762 << (UO->getOpcode() == UO_Plus ? "+" : "-")
11763 << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
11764 }
11765 }
11766
11767 if (ConvTy == Compatible) {
11768 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) {
11769 // Warn about retain cycles where a block captures the LHS, but
11770 // not if the LHS is a simple variable into which the block is
11771 // being stored...unless that variable can be captured by reference!
11772 const Expr *InnerLHS = LHSExpr->IgnoreParenCasts();
11773 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InnerLHS);
11774 if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>())
11775 checkRetainCycles(LHSExpr, RHS.get());
11776 }
11777
11778 if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong ||
11779 LHSType.isNonWeakInMRRWithObjCWeak(Context)) {
11780 // It is safe to assign a weak reference into a strong variable.
11781 // Although this code can still have problems:
11782 // id x = self.weakProp;
11783 // id y = self.weakProp;
11784 // we do not warn to warn spuriously when 'x' and 'y' are on separate
11785 // paths through the function. This should be revisited if
11786 // -Wrepeated-use-of-weak is made flow-sensitive.
11787 // For ObjCWeak only, we do not warn if the assign is to a non-weak
11788 // variable, which will be valid for the current autorelease scope.
11789 if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
11790 RHS.get()->getBeginLoc()))
11791 getCurFunction()->markSafeWeakUse(RHS.get());
11792
11793 } else if (getLangOpts().ObjCAutoRefCount || getLangOpts().ObjCWeak) {
11794 checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get());
11795 }
11796 }
11797 } else {
11798 // Compound assignment "x += y"
11799 ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType);
11800 }
11801
11802 if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType,
11803 RHS.get(), AA_Assigning))
11804 return QualType();
11805
11806 CheckForNullPointerDereference(*this, LHSExpr);
11807
11808 // C99 6.5.16p3: The type of an assignment expression is the type of the
11809 // left operand unless the left operand has qualified type, in which case
11810 // it is the unqualified version of the type of the left operand.
11811 // C99 6.5.16.1p2: In simple assignment, the value of the right operand
11812 // is converted to the type of the assignment expression (above).
11813 // C++ 5.17p1: the type of the assignment expression is that of its left
11814 // operand.
11815 return (getLangOpts().CPlusPlus
11816 ? LHSType : LHSType.getUnqualifiedType());
11817}
11818
11819// Only ignore explicit casts to void.
11820static bool IgnoreCommaOperand(const Expr *E) {
11821 E = E->IgnoreParens();
11822
11823 if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
11824 if (CE->getCastKind() == CK_ToVoid) {
11825 return true;
11826 }
11827
11828 // static_cast<void> on a dependent type will not show up as CK_ToVoid.
11829 if (CE->getCastKind() == CK_Dependent && E->getType()->isVoidType() &&
11830 CE->getSubExpr()->getType()->isDependentType()) {
11831 return true;
11832 }
11833 }
11834
11835 return false;
11836}
11837
11838// Look for instances where it is likely the comma operator is confused with
11839// another operator. There is a whitelist of acceptable expressions for the
11840// left hand side of the comma operator, otherwise emit a warning.
11841void Sema::DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc) {
11842 // No warnings in macros
11843 if (Loc.isMacroID())
11844 return;
11845
11846 // Don't warn in template instantiations.
11847 if (inTemplateInstantiation())
11848 return;
11849
11850 // Scope isn't fine-grained enough to whitelist the specific cases, so
11851 // instead, skip more than needed, then call back into here with the
11852 // CommaVisitor in SemaStmt.cpp.
11853 // The whitelisted locations are the initialization and increment portions
11854 // of a for loop. The additional checks are on the condition of
11855 // if statements, do/while loops, and for loops.
11856 // Differences in scope flags for C89 mode requires the extra logic.
11857 const unsigned ForIncrementFlags =
11858 getLangOpts().C99 || getLangOpts().CPlusPlus
11859 ? Scope::ControlScope | Scope::ContinueScope | Scope::BreakScope
11860 : Scope::ContinueScope | Scope::BreakScope;
11861 const unsigned ForInitFlags = Scope::ControlScope | Scope::DeclScope;
11862 const unsigned ScopeFlags = getCurScope()->getFlags();
11863 if ((ScopeFlags & ForIncrementFlags) == ForIncrementFlags ||
11864 (ScopeFlags & ForInitFlags) == ForInitFlags)
11865 return;
11866
11867 // If there are multiple comma operators used together, get the RHS of the
11868 // of the comma operator as the LHS.
11869 while (const BinaryOperator *BO = dyn_cast<BinaryOperator>(LHS)) {
11870 if (BO->getOpcode() != BO_Comma)
11871 break;
11872 LHS = BO->getRHS();
11873 }
11874
11875 // Only allow some expressions on LHS to not warn.
11876 if (IgnoreCommaOperand(LHS))
11877 return;
11878
11879 Diag(Loc, diag::warn_comma_operator);
11880 Diag(LHS->getBeginLoc(), diag::note_cast_to_void)
11881 << LHS->getSourceRange()
11882 << FixItHint::CreateInsertion(LHS->getBeginLoc(),
11883 LangOpts.CPlusPlus ? "static_cast<void>("
11884 : "(void)(")
11885 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(LHS->getEndLoc()),
11886 ")");
11887}
11888
11889// C99 6.5.17
11890static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS,
11891 SourceLocation Loc) {
11892 LHS = S.CheckPlaceholderExpr(LHS.get());
11893 RHS = S.CheckPlaceholderExpr(RHS.get());
11894 if (LHS.isInvalid() || RHS.isInvalid())
11895 return QualType();
11896
11897 // C's comma performs lvalue conversion (C99 6.3.2.1) on both its
11898 // operands, but not unary promotions.
11899 // C++'s comma does not do any conversions at all (C++ [expr.comma]p1).
11900
11901 // So we treat the LHS as a ignored value, and in C++ we allow the
11902 // containing site to determine what should be done with the RHS.
11903 LHS = S.IgnoredValueConversions(LHS.get());
11904 if (LHS.isInvalid())
11905 return QualType();
11906
11907 S.DiagnoseUnusedExprResult(LHS.get());
11908
11909 if (!S.getLangOpts().CPlusPlus) {
11910 RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
11911 if (RHS.isInvalid())
11912 return QualType();
11913 if (!RHS.get()->getType()->isVoidType())
11914 S.RequireCompleteType(Loc, RHS.get()->getType(),
11915 diag::err_incomplete_type);
11916 }
11917
11918 if (!S.getDiagnostics().isIgnored(diag::warn_comma_operator, Loc))
11919 S.DiagnoseCommaOperator(LHS.get(), Loc);
11920
11921 return RHS.get()->getType();
11922}
11923
11924/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
11925/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
11926static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op,
11927 ExprValueKind &VK,
11928 ExprObjectKind &OK,
11929 SourceLocation OpLoc,
11930 bool IsInc, bool IsPrefix) {
11931 if (Op->isTypeDependent())
11932 return S.Context.DependentTy;
11933
11934 QualType ResType = Op->getType();
11935 // Atomic types can be used for increment / decrement where the non-atomic
11936 // versions can, so ignore the _Atomic() specifier for the purpose of
11937 // checking.
11938 if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
11939 ResType = ResAtomicType->getValueType();
11940
11941 assert(!ResType.isNull() && "no type for increment/decrement expression");
11942
11943 if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) {
11944 // Decrement of bool is not allowed.
11945 if (!IsInc) {
11946 S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange();
11947 return QualType();
11948 }
11949 // Increment of bool sets it to true, but is deprecated.
11950 S.Diag(OpLoc, S.getLangOpts().CPlusPlus17 ? diag::ext_increment_bool
11951 : diag::warn_increment_bool)
11952 << Op->getSourceRange();
11953 } else if (S.getLangOpts().CPlusPlus && ResType->isEnumeralType()) {
11954 // Error on enum increments and decrements in C++ mode
11955 S.Diag(OpLoc, diag::err_increment_decrement_enum) << IsInc << ResType;
11956 return QualType();
11957 } else if (ResType->isRealType()) {
11958 // OK!
11959 } else if (ResType->isPointerType()) {
11960 // C99 6.5.2.4p2, 6.5.6p2
11961 if (!checkArithmeticOpPointerOperand(S, OpLoc, Op))
11962 return QualType();
11963 } else if (ResType->isObjCObjectPointerType()) {
11964 // On modern runtimes, ObjC pointer arithmetic is forbidden.
11965 // Otherwise, we just need a complete type.
11966 if (checkArithmeticIncompletePointerType(S, OpLoc, Op) ||
11967 checkArithmeticOnObjCPointer(S, OpLoc, Op))
11968 return QualType();
11969 } else if (ResType->isAnyComplexType()) {
11970 // C99 does not support ++/-- on complex types, we allow as an extension.
11971 S.Diag(OpLoc, diag::ext_integer_increment_complex)
11972 << ResType << Op->getSourceRange();
11973 } else if (ResType->isPlaceholderType()) {
11974 ExprResult PR = S.CheckPlaceholderExpr(Op);
11975 if (PR.isInvalid()) return QualType();
11976 return CheckIncrementDecrementOperand(S, PR.get(), VK, OK, OpLoc,
11977 IsInc, IsPrefix);
11978 } else if (S.getLangOpts().AltiVec && ResType->isVectorType()) {
11979 // OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 )
11980 } else if (S.getLangOpts().ZVector && ResType->isVectorType() &&
11981 (ResType->getAs<VectorType>()->getVectorKind() !=
11982 VectorType::AltiVecBool)) {
11983 // The z vector extensions allow ++ and -- for non-bool vectors.
11984 } else if(S.getLangOpts().OpenCL && ResType->isVectorType() &&
11985 ResType->getAs<VectorType>()->getElementType()->isIntegerType()) {
11986 // OpenCL V1.2 6.3 says dec/inc ops operate on integer vector types.
11987 } else {
11988 S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement)
11989 << ResType << int(IsInc) << Op->getSourceRange();
11990 return QualType();
11991 }
11992 // At this point, we know we have a real, complex or pointer type.
11993 // Now make sure the operand is a modifiable lvalue.
11994 if (CheckForModifiableLvalue(Op, OpLoc, S))
11995 return QualType();
11996 // In C++, a prefix increment is the same type as the operand. Otherwise
11997 // (in C or with postfix), the increment is the unqualified type of the
11998 // operand.
11999 if (IsPrefix && S.getLangOpts().CPlusPlus) {
12000 VK = VK_LValue;
12001 OK = Op->getObjectKind();
12002 return ResType;
12003 } else {
12004 VK = VK_RValue;
12005 return ResType.getUnqualifiedType();
12006 }
12007}
12008
12009
12010/// getPrimaryDecl - Helper function for CheckAddressOfOperand().
12011/// This routine allows us to typecheck complex/recursive expressions
12012/// where the declaration is needed for type checking. We only need to
12013/// handle cases when the expression references a function designator
12014/// or is an lvalue. Here are some examples:
12015/// - &(x) => x
12016/// - &*****f => f for f a function designator.
12017/// - &s.xx => s
12018/// - &s.zz[1].yy -> s, if zz is an array
12019/// - *(x + 1) -> x, if x is an array
12020/// - &"123"[2] -> 0
12021/// - & __real__ x -> x
12022static ValueDecl *getPrimaryDecl(Expr *E) {
12023 switch (E->getStmtClass()) {
12024 case Stmt::DeclRefExprClass:
12025 return cast<DeclRefExpr>(E)->getDecl();
12026 case Stmt::MemberExprClass:
12027 // If this is an arrow operator, the address is an offset from
12028 // the base's value, so the object the base refers to is
12029 // irrelevant.
12030 if (cast<MemberExpr>(E)->isArrow())
12031 return nullptr;
12032 // Otherwise, the expression refers to a part of the base
12033 return getPrimaryDecl(cast<MemberExpr>(E)->getBase());
12034 case Stmt::ArraySubscriptExprClass: {
12035 // FIXME: This code shouldn't be necessary! We should catch the implicit
12036 // promotion of register arrays earlier.
12037 Expr* Base = cast<ArraySubscriptExpr>(E)->getBase();
12038 if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) {
12039 if (ICE->getSubExpr()->getType()->isArrayType())
12040 return getPrimaryDecl(ICE->getSubExpr());
12041 }
12042 return nullptr;
12043 }
12044 case Stmt::UnaryOperatorClass: {
12045 UnaryOperator *UO = cast<UnaryOperator>(E);
12046
12047 switch(UO->getOpcode()) {
12048 case UO_Real:
12049 case UO_Imag:
12050 case UO_Extension:
12051 return getPrimaryDecl(UO->getSubExpr());
12052 default:
12053 return nullptr;
12054 }
12055 }
12056 case Stmt::ParenExprClass:
12057 return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr());
12058 case Stmt::ImplicitCastExprClass:
12059 // If the result of an implicit cast is an l-value, we care about
12060 // the sub-expression; otherwise, the result here doesn't matter.
12061 return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr());
12062 default:
12063 return nullptr;
12064 }
12065}
12066
12067namespace {
12068 enum {
12069 AO_Bit_Field = 0,
12070 AO_Vector_Element = 1,
12071 AO_Property_Expansion = 2,
12072 AO_Register_Variable = 3,
12073 AO_No_Error = 4
12074 };
12075}
12076/// Diagnose invalid operand for address of operations.
12077///
12078/// \param Type The type of operand which cannot have its address taken.
12079static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc,
12080 Expr *E, unsigned Type) {
12081 S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange();
12082}
12083
12084static ASTContext::PointerInterpretationKind
12085pointerKindForBaseExpr(const ASTContext &Context, const Expr *Base, bool WasMemberExpr = false) {
12086 if (auto *mr = dyn_cast<MemberExpr>(Base))
12087 return pointerKindForBaseExpr(Context, mr->getBase(), true);
12088 else if (auto *as = dyn_cast<ArraySubscriptExpr>(Base))
12089 // We need IgnoreImpCasts() here to strip the ArrayToPointerDecay
12090 return pointerKindForBaseExpr(Context, as->getBase()->IgnoreImpCasts(), true);
12091
12092 // If we are just taking the address of something that happens to be a
12093 // capability we should not infer that the result is a capability. This only
12094 // applies if there is a least one level of MemberExpr/ArraySubscriptExpr
12095 // For example the following should be an error in the hybrid ABI:
12096 // void * __capability b;
12097 // void *__capability *__capability c = &b;
12098 if (!WasMemberExpr)
12099 return ASTContext::PIK_Default;
12100 // If the basetype is __uintcap_t we don't want to treat the result as a
12101 // capability (such as in uintcap_t foo; return &foo;)
12102 if (Base->getType()->isCHERICapabilityType(Context, /*IncludeIntCap=*/false))
12103 return ASTContext::PIK_Capability;
12104 return ASTContext::PIK_Default;
12105}
12106
12107/// CheckAddressOfOperand - The operand of & must be either a function
12108/// designator or an lvalue designating an object. If it is an lvalue, the
12109/// object cannot be declared with storage class register or be a bit field.
12110/// Note: The usual conversions are *not* applied to the operand of the &
12111/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue.
12112/// In C++, the operand might be an overloaded function name, in which case
12113/// we allow the '&' but retain the overloaded-function type.
12114QualType Sema::CheckAddressOfOperand(ExprResult &OrigOp, SourceLocation OpLoc) {
12115 if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){
12116 if (PTy->getKind() == BuiltinType::Overload) {
12117 Expr *E = OrigOp.get()->IgnoreParens();
12118 if (!isa<OverloadExpr>(E)) {
12119 assert(cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf);
12120 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof_addrof_function)
12121 << OrigOp.get()->getSourceRange();
12122 return QualType();
12123 }
12124
12125 OverloadExpr *Ovl = cast<OverloadExpr>(E);
12126 if (isa<UnresolvedMemberExpr>(Ovl))
12127 if (!ResolveSingleFunctionTemplateSpecialization(Ovl)) {
12128 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
12129 << OrigOp.get()->getSourceRange();
12130 return QualType();
12131 }
12132
12133 return Context.OverloadTy;
12134 }
12135
12136 if (PTy->getKind() == BuiltinType::UnknownAny)
12137 return Context.UnknownAnyTy;
12138
12139 if (PTy->getKind() == BuiltinType::BoundMember) {
12140 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
12141 << OrigOp.get()->getSourceRange();
12142 return QualType();
12143 }
12144
12145 OrigOp = CheckPlaceholderExpr(OrigOp.get());
12146 if (OrigOp.isInvalid()) return QualType();
12147 }
12148
12149 if (OrigOp.get()->isTypeDependent())
12150 return Context.DependentTy;
12151
12152 assert(!OrigOp.get()->getType()->isPlaceholderType());
12153
12154 // Make sure to ignore parentheses in subsequent checks
12155 Expr *op = OrigOp.get()->IgnoreParens();
12156
12157 // In OpenCL captures for blocks called as lambda functions
12158 // are located in the private address space. Blocks used in
12159 // enqueue_kernel can be located in a different address space
12160 // depending on a vendor implementation. Thus preventing
12161 // taking an address of the capture to avoid invalid AS casts.
12162 if (LangOpts.OpenCL) {
12163 auto* VarRef = dyn_cast<DeclRefExpr>(op);
12164 if (VarRef && VarRef->refersToEnclosingVariableOrCapture()) {
12165 Diag(op->getExprLoc(), diag::err_opencl_taking_address_capture);
12166 return QualType();
12167 }
12168 }
12169
12170 if (getLangOpts().C99) {
12171 // Implement C99-only parts of addressof rules.
12172 if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) {
12173 if (uOp->getOpcode() == UO_Deref)
12174 // Per C99 6.5.3.2, the address of a deref always returns a valid result
12175 // (assuming the deref expression is valid).
12176 return uOp->getSubExpr()->getType();
12177 }
12178 // Technically, there should be a check for array subscript
12179 // expressions here, but the result of one is always an lvalue anyway.
12180 }
12181 ValueDecl *dcl = getPrimaryDecl(op);
12182
12183 if (auto *FD = dyn_cast_or_null<FunctionDecl>(dcl))
12184 if (!checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
12185 op->getBeginLoc()))
12186 return QualType();
12187
12188 Expr::LValueClassification lval = op->ClassifyLValue(Context);
12189 unsigned AddressOfError = AO_No_Error;
12190
12191 if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) {
12192 bool sfinae = (bool)isSFINAEContext();
12193 Diag(OpLoc, isSFINAEContext() ? diag::err_typecheck_addrof_temporary
12194 : diag::ext_typecheck_addrof_temporary)
12195 << op->getType() << op->getSourceRange();
12196 if (sfinae)
12197 return QualType();
12198 // Materialize the temporary as an lvalue so that we can take its address.
12199 OrigOp = op =
12200 CreateMaterializeTemporaryExpr(op->getType(), OrigOp.get(), true);
12201 } else if (isa<ObjCSelectorExpr>(op)) {
12202 return Context.getPointerType(op->getType());
12203 } else if (lval == Expr::LV_MemberFunction) {
12204 // If it's an instance method, make a member pointer.
12205 // The expression must have exactly the form &A::foo.
12206
12207 // If the underlying expression isn't a decl ref, give up.
12208 if (!isa<DeclRefExpr>(op)) {
12209 Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
12210 << OrigOp.get()->getSourceRange();
12211 return QualType();
12212 }
12213 DeclRefExpr *DRE = cast<DeclRefExpr>(op);
12214 CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl());
12215
12216 // The id-expression was parenthesized.
12217 if (OrigOp.get() != DRE) {
12218 Diag(OpLoc, diag::err_parens_pointer_member_function)
12219 << OrigOp.get()->getSourceRange();
12220
12221 // The method was named without a qualifier.
12222 } else if (!DRE->getQualifier()) {
12223 if (MD->getParent()->getName().empty())
12224 Diag(OpLoc, diag::err_unqualified_pointer_member_function)
12225 << op->getSourceRange();
12226 else {
12227 SmallString<32> Str;
12228 StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Str);
12229 Diag(OpLoc, diag::err_unqualified_pointer_member_function)
12230 << op->getSourceRange()
12231 << FixItHint::CreateInsertion(op->getSourceRange().getBegin(), Qual);
12232 }
12233 }
12234
12235 // Taking the address of a dtor is illegal per C++ [class.dtor]p2.
12236 if (isa<CXXDestructorDecl>(MD))
12237 Diag(OpLoc, diag::err_typecheck_addrof_dtor) << op->getSourceRange();
12238
12239 QualType MPTy = Context.getMemberPointerType(
12240 op->getType(), Context.getTypeDeclType(MD->getParent()).getTypePtr());
12241 // Under the MS ABI, lock down the inheritance model now.
12242 if (Context.getTargetInfo().getCXXABI().isMicrosoft())
12243 (void)isCompleteType(OpLoc, MPTy);
12244 return MPTy;
12245 } else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) {
12246 // C99 6.5.3.2p1
12247 // The operand must be either an l-value or a function designator
12248 if (!op->getType()->isFunctionType()) {
12249 // Use a special diagnostic for loads from property references.
12250 if (isa<PseudoObjectExpr>(op)) {
12251 AddressOfError = AO_Property_Expansion;
12252 } else {
12253 Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof)
12254 << op->getType() << op->getSourceRange();
12255 return QualType();
12256 }
12257 }
12258 } else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1
12259 // The operand cannot be a bit-field
12260 AddressOfError = AO_Bit_Field;
12261 } else if (op->getObjectKind() == OK_VectorComponent) {
12262 // The operand cannot be an element of a vector
12263 AddressOfError = AO_Vector_Element;
12264 } else if (dcl) { // C99 6.5.3.2p1
12265 // We have an lvalue with a decl. Make sure the decl is not declared
12266 // with the register storage-class specifier.
12267 if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) {
12268 // in C++ it is not error to take address of a register
12269 // variable (c++03 7.1.1P3)
12270 if (vd->getStorageClass() == SC_Register &&
12271 !getLangOpts().CPlusPlus) {
12272 AddressOfError = AO_Register_Variable;
12273 }
12274 } else if (isa<MSPropertyDecl>(dcl)) {
12275 AddressOfError = AO_Property_Expansion;
12276 } else if (isa<FunctionTemplateDecl>(dcl)) {
12277 return Context.OverloadTy;
12278 } else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) {
12279 // Okay: we can take the address of a field.
12280 // Could be a pointer to member, though, if there is an explicit
12281 // scope qualifier for the class.
12282 if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) {
12283 DeclContext *Ctx = dcl->getDeclContext();
12284 if (Ctx && Ctx->isRecord()) {
12285 if (dcl->getType()->isReferenceType()) {
12286 Diag(OpLoc,
12287 diag::err_cannot_form_pointer_to_member_of_reference_type)
12288 << dcl->getDeclName() << dcl->getType();
12289 return QualType();
12290 }
12291
12292 while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion())
12293 Ctx = Ctx->getParent();
12294
12295 QualType MPTy = Context.getMemberPointerType(
12296 op->getType(),
12297 Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr());
12298 // Under the MS ABI, lock down the inheritance model now.
12299 if (Context.getTargetInfo().getCXXABI().isMicrosoft())
12300 (void)isCompleteType(OpLoc, MPTy);
12301 return MPTy;
12302 }
12303 }
12304 } else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl) &&
12305 !isa<BindingDecl>(dcl))
12306 llvm_unreachable("Unknown/unexpected decl type");
12307 }
12308
12309 if (AddressOfError != AO_No_Error) {
12310 diagnoseAddressOfInvalidType(*this, OpLoc, op, AddressOfError);
12311 return QualType();
12312 }
12313
12314 if (lval == Expr::LV_IncompleteVoidType) {
12315 // Taking the address of a void variable is technically illegal, but we
12316 // allow it in cases which are otherwise valid.
12317 // Example: "extern void x; void* y = &x;".
12318 Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange();
12319 }
12320
12321 // If the operand has type "type", the result has type "pointer to type".
12322 if (op->getType()->isObjCObjectType())
12323 return Context.getObjCObjectPointerType(op->getType());
12324
12325 CheckAddressOfPackedMember(op);
12326
12327 ASTContext::PointerInterpretationKind PIK =
12328 pointerKindForBaseExpr(Context, op);
12329 return Context.getPointerType(op->getType(), PIK);
12330}
12331
12332static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
12333 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Exp);
12334 if (!DRE)
12335 return;
12336 const Decl *D = DRE->getDecl();
12337 if (!D)
12338 return;
12339 const ParmVarDecl *Param = dyn_cast<ParmVarDecl>(D);
12340 if (!Param)
12341 return;
12342 if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(Param->getDeclContext()))
12343 if (!FD->hasAttr<NonNullAttr>() && !Param->hasAttr<NonNullAttr>())
12344 return;
12345 if (FunctionScopeInfo *FD = S.getCurFunction())
12346 if (!FD->ModifiedNonNullParams.count(Param))
12347 FD->ModifiedNonNullParams.insert(Param);
12348}
12349
12350/// CheckIndirectionOperand - Type check unary indirection (prefix '*').
12351static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
12352 SourceLocation OpLoc) {
12353 if (Op->isTypeDependent())
12354 return S.Context.DependentTy;
12355
12356 ExprResult ConvResult = S.UsualUnaryConversions(Op);
12357 if (ConvResult.isInvalid())
12358 return QualType();
12359 Op = ConvResult.get();
12360 QualType OpTy = Op->getType();
12361 QualType Result;
12362
12363 if (isa<CXXReinterpretCastExpr>(Op)) {
12364 QualType OpOrigType = Op->IgnoreParenCasts()->getType();
12365 S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true,
12366 Op->getSourceRange());
12367 }
12368
12369 if (const PointerType *PT = OpTy->getAs<PointerType>())
12370 {
12371 Result = PT->getPointeeType();
12372 }
12373 else if (const ObjCObjectPointerType *OPT =
12374 OpTy->getAs<ObjCObjectPointerType>())
12375 Result = OPT->getPointeeType();
12376 else {
12377 ExprResult PR = S.CheckPlaceholderExpr(Op);
12378 if (PR.isInvalid()) return QualType();
12379 if (PR.get() != Op)
12380 return CheckIndirectionOperand(S, PR.get(), VK, OpLoc);
12381 }
12382
12383 if (Result.isNull()) {
12384 S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer)
12385 << OpTy << Op->getSourceRange();
12386 return QualType();
12387 }
12388
12389 // Note that per both C89 and C99, indirection is always legal, even if Result
12390 // is an incomplete type or void. It would be possible to warn about
12391 // dereferencing a void pointer, but it's completely well-defined, and such a
12392 // warning is unlikely to catch any mistakes. In C++, indirection is not valid
12393 // for pointers to 'void' but is fine for any other pointer type:
12394 //
12395 // C++ [expr.unary.op]p1:
12396 // [...] the expression to which [the unary * operator] is applied shall
12397 // be a pointer to an object type, or a pointer to a function type
12398 if (S.getLangOpts().CPlusPlus && Result->isVoidType())
12399 S.Diag(OpLoc, diag::ext_typecheck_indirection_through_void_pointer)
12400 << OpTy << Op->getSourceRange();
12401
12402 // Dereferences are usually l-values...
12403 VK = VK_LValue;
12404
12405 // ...except that certain expressions are never l-values in C.
12406 if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType())
12407 VK = VK_RValue;
12408
12409 return Result;
12410}
12411
12412BinaryOperatorKind Sema::ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind) {
12413 BinaryOperatorKind Opc;
12414 switch (Kind) {
12415 default: llvm_unreachable("Unknown binop!");
12416 case tok::periodstar: Opc = BO_PtrMemD; break;
12417 case tok::arrowstar: Opc = BO_PtrMemI; break;
12418 case tok::star: Opc = BO_Mul; break;
12419 case tok::slash: Opc = BO_Div; break;
12420 case tok::percent: Opc = BO_Rem; break;
12421 case tok::plus: Opc = BO_Add; break;
12422 case tok::minus: Opc = BO_Sub; break;
12423 case tok::lessless: Opc = BO_Shl; break;
12424 case tok::greatergreater: Opc = BO_Shr; break;
12425 case tok::lessequal: Opc = BO_LE; break;
12426 case tok::less: Opc = BO_LT; break;
12427 case tok::greaterequal: Opc = BO_GE; break;
12428 case tok::greater: Opc = BO_GT; break;
12429 case tok::exclaimequal: Opc = BO_NE; break;
12430 case tok::equalequal: Opc = BO_EQ; break;
12431 case tok::spaceship: Opc = BO_Cmp; break;
12432 case tok::amp: Opc = BO_And; break;
12433 case tok::caret: Opc = BO_Xor; break;
12434 case tok::pipe: Opc = BO_Or; break;
12435 case tok::ampamp: Opc = BO_LAnd; break;
12436 case tok::pipepipe: Opc = BO_LOr; break;
12437 case tok::equal: Opc = BO_Assign; break;
12438 case tok::starequal: Opc = BO_MulAssign; break;
12439 case tok::slashequal: Opc = BO_DivAssign; break;
12440 case tok::percentequal: Opc = BO_RemAssign; break;
12441 case tok::plusequal: Opc = BO_AddAssign; break;
12442 case tok::minusequal: Opc = BO_SubAssign; break;
12443 case tok::lesslessequal: Opc = BO_ShlAssign; break;
12444 case tok::greatergreaterequal: Opc = BO_ShrAssign; break;
12445 case tok::ampequal: Opc = BO_AndAssign; break;
12446 case tok::caretequal: Opc = BO_XorAssign; break;
12447 case tok::pipeequal: Opc = BO_OrAssign; break;
12448 case tok::comma: Opc = BO_Comma; break;
12449 }
12450 return Opc;
12451}
12452
12453static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
12454 tok::TokenKind Kind) {
12455 UnaryOperatorKind Opc;
12456 switch (Kind) {
12457 default: llvm_unreachable("Unknown unary op!");
12458 case tok::plusplus: Opc = UO_PreInc; break;
12459 case tok::minusminus: Opc = UO_PreDec; break;
12460 case tok::amp: Opc = UO_AddrOf; break;
12461 case tok::star: Opc = UO_Deref; break;
12462 case tok::plus: Opc = UO_Plus; break;
12463 case tok::minus: Opc = UO_Minus; break;
12464 case tok::tilde: Opc = UO_Not; break;
12465 case tok::exclaim: Opc = UO_LNot; break;
12466 case tok::kw___real: Opc = UO_Real; break;
12467 case tok::kw___imag: Opc = UO_Imag; break;
12468 case tok::kw___extension__: Opc = UO_Extension; break;
12469 }
12470 return Opc;
12471}
12472
12473/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
12474/// This warning suppressed in the event of macro expansions.
12475static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
12476 SourceLocation OpLoc, bool IsBuiltin) {
12477 if (S.inTemplateInstantiation())
12478 return;
12479 if (S.isUnevaluatedContext())
12480 return;
12481 if (OpLoc.isInvalid() || OpLoc.isMacroID())
12482 return;
12483 LHSExpr = LHSExpr->IgnoreParenImpCasts();
12484 RHSExpr = RHSExpr->IgnoreParenImpCasts();
12485 const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr);
12486 const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr);
12487 if (!LHSDeclRef || !RHSDeclRef ||
12488 LHSDeclRef->getLocation().isMacroID() ||
12489 RHSDeclRef->getLocation().isMacroID())
12490 return;
12491 const ValueDecl *LHSDecl =
12492 cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl());
12493 const ValueDecl *RHSDecl =
12494 cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl());
12495 if (LHSDecl != RHSDecl)
12496 return;
12497 if (LHSDecl->getType().isVolatileQualified())
12498 return;
12499 if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
12500 if (RefTy->getPointeeType().isVolatileQualified())
12501 return;
12502
12503 S.Diag(OpLoc, IsBuiltin ? diag::warn_self_assignment_builtin
12504 : diag::warn_self_assignment_overloaded)
12505 << LHSDeclRef->getType() << LHSExpr->getSourceRange()
12506 << RHSExpr->getSourceRange();
12507}
12508
12509/// Check if a bitwise-& is performed on an Objective-C pointer. This
12510/// is usually indicative of introspection within the Objective-C pointer.
12511static void checkObjCPointerIntrospection(Sema &S, ExprResult &L, ExprResult &R,
12512 SourceLocation OpLoc) {
12513 if (!S.getLangOpts().ObjC)
12514 return;
12515
12516 const Expr *ObjCPointerExpr = nullptr, *OtherExpr = nullptr;
12517 const Expr *LHS = L.get();
12518 const Expr *RHS = R.get();
12519
12520 if (LHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
12521 ObjCPointerExpr = LHS;
12522 OtherExpr = RHS;
12523 }
12524 else if (RHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
12525 ObjCPointerExpr = RHS;
12526 OtherExpr = LHS;
12527 }
12528
12529 // This warning is deliberately made very specific to reduce false
12530 // positives with logic that uses '&' for hashing. This logic mainly
12531 // looks for code trying to introspect into tagged pointers, which
12532 // code should generally never do.
12533 if (ObjCPointerExpr && isa<IntegerLiteral>(OtherExpr->IgnoreParenCasts())) {
12534 unsigned Diag = diag::warn_objc_pointer_masking;
12535 // Determine if we are introspecting the result of performSelectorXXX.
12536 const Expr *Ex = ObjCPointerExpr->IgnoreParenCasts();
12537 // Special case messages to -performSelector and friends, which
12538 // can return non-pointer values boxed in a pointer value.
12539 // Some clients may wish to silence warnings in this subcase.
12540 if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(Ex)) {
12541 Selector S = ME->getSelector();
12542 StringRef SelArg0 = S.getNameForSlot(0);
12543 if (SelArg0.startswith("performSelector"))
12544 Diag = diag::warn_objc_pointer_masking_performSelector;
12545 }
12546
12547 S.Diag(OpLoc, Diag)
12548 << ObjCPointerExpr->getSourceRange();
12549 }
12550}
12551
12552static NamedDecl *getDeclFromExpr(Expr *E) {
12553 if (!E)
12554 return nullptr;
12555 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
12556 return DRE->getDecl();
12557 if (auto *ME = dyn_cast<MemberExpr>(E))
12558 return ME->getMemberDecl();
12559 if (auto *IRE = dyn_cast<ObjCIvarRefExpr>(E))
12560 return IRE->getDecl();
12561 return nullptr;
12562}
12563
12564// This helper function promotes a binary operator's operands (which are of a
12565// half vector type) to a vector of floats and then truncates the result to
12566// a vector of either half or short.
12567static ExprResult convertHalfVecBinOp(Sema &S, ExprResult LHS, ExprResult RHS,
12568 BinaryOperatorKind Opc, QualType ResultTy,
12569 ExprValueKind VK, ExprObjectKind OK,
12570 bool IsCompAssign, SourceLocation OpLoc,
12571 FPOptions FPFeatures) {
12572 auto &Context = S.getASTContext();
12573 assert((isVector(ResultTy, Context.HalfTy) ||
12574 isVector(ResultTy, Context.ShortTy)) &&
12575 "Result must be a vector of half or short");
12576 assert(isVector(LHS.get()->getType(), Context.HalfTy) &&
12577 isVector(RHS.get()->getType(), Context.HalfTy) &&
12578 "both operands expected to be a half vector");
12579
12580 RHS = convertVector(RHS.get(), Context.FloatTy, S);
12581 QualType BinOpResTy = RHS.get()->getType();
12582
12583 // If Opc is a comparison, ResultType is a vector of shorts. In that case,
12584 // change BinOpResTy to a vector of ints.
12585 if (isVector(ResultTy, Context.ShortTy))
12586 BinOpResTy = S.GetSignedVectorType(BinOpResTy);
12587
12588 if (IsCompAssign)
12589 return new (Context) CompoundAssignOperator(
12590 LHS.get(), RHS.get(), Opc, ResultTy, VK, OK, BinOpResTy, BinOpResTy,
12591 OpLoc, FPFeatures);
12592
12593 LHS = convertVector(LHS.get(), Context.FloatTy, S);
12594 auto *BO = new (Context) BinaryOperator(LHS.get(), RHS.get(), Opc, BinOpResTy,
12595 VK, OK, OpLoc, FPFeatures);
12596 return convertVector(BO, ResultTy->getAs<VectorType>()->getElementType(), S);
12597}
12598
12599static std::pair<ExprResult, ExprResult>
12600CorrectDelayedTyposInBinOp(Sema &S, BinaryOperatorKind Opc, Expr *LHSExpr,
12601 Expr *RHSExpr) {
12602 ExprResult LHS = LHSExpr, RHS = RHSExpr;
12603 if (!S.getLangOpts().CPlusPlus) {
12604 // C cannot handle TypoExpr nodes on either side of a binop because it
12605 // doesn't handle dependent types properly, so make sure any TypoExprs have
12606 // been dealt with before checking the operands.
12607 LHS = S.CorrectDelayedTyposInExpr(LHS);
12608 RHS = S.CorrectDelayedTyposInExpr(RHS, [Opc, LHS](Expr *E) {
12609 if (Opc != BO_Assign)
12610 return ExprResult(E);
12611 // Avoid correcting the RHS to the same Expr as the LHS.
12612 Decl *D = getDeclFromExpr(E);
12613 return (D && D == getDeclFromExpr(LHS.get())) ? ExprError() : E;
12614 });
12615 }
12616 return std::make_pair(LHS, RHS);
12617}
12618
12619/// Returns true if conversion between vectors of halfs and vectors of floats
12620/// is needed.
12621static bool needsConversionOfHalfVec(bool OpRequiresConversion, ASTContext &Ctx,
12622 QualType SrcType) {
12623 return OpRequiresConversion && !Ctx.getLangOpts().NativeHalfType &&
12624 !Ctx.getTargetInfo().useFP16ConversionIntrinsics() &&
12625 isVector(SrcType, Ctx.HalfTy);
12626}
12627
12628/// CreateBuiltinBinOp - Creates a new built-in binary operation with
12629/// operator @p Opc at location @c TokLoc. This routine only supports
12630/// built-in operations; ActOnBinOp handles overloaded operators.
12631ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
12632 BinaryOperatorKind Opc,
12633 Expr *LHSExpr, Expr *RHSExpr) {
12634 if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(RHSExpr)) {
12635 // The syntax only allows initializer lists on the RHS of assignment,
12636 // so we don't need to worry about accepting invalid code for
12637 // non-assignment operators.
12638 // C++11 5.17p9:
12639 // The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning
12640 // of x = {} is x = T().
12641 InitializationKind Kind = InitializationKind::CreateDirectList(
12642 RHSExpr->getBeginLoc(), RHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
12643 InitializedEntity Entity =
12644 InitializedEntity::InitializeTemporary(LHSExpr->getType());
12645 InitializationSequence InitSeq(*this, Entity, Kind, RHSExpr);
12646 ExprResult Init = InitSeq.Perform(*this, Entity, Kind, RHSExpr);
12647 if (Init.isInvalid())
12648 return Init;
12649 RHSExpr = Init.get();
12650 }
12651
12652 ExprResult LHS = LHSExpr, RHS = RHSExpr;
12653 QualType ResultTy; // Result type of the binary operator.
12654 // The following two variables are used for compound assignment operators
12655 QualType CompLHSTy; // Type of LHS after promotions for computation
12656 QualType CompResultTy; // Type of computation result
12657 ExprValueKind VK = VK_RValue;
12658 ExprObjectKind OK = OK_Ordinary;
12659 bool ConvertHalfVec = false;
12660
12661 std::tie(LHS, RHS) = CorrectDelayedTyposInBinOp(*this, Opc, LHSExpr, RHSExpr);
12662 if (!LHS.isUsable() || !RHS.isUsable())
12663 return ExprError();
12664
12665 if (getLangOpts().OpenCL) {
12666 QualType LHSTy = LHSExpr->getType();
12667 QualType RHSTy = RHSExpr->getType();
12668 // OpenCLC v2.0 s6.13.11.1 allows atomic variables to be initialized by
12669 // the ATOMIC_VAR_INIT macro.
12670 if (LHSTy->isAtomicType() || RHSTy->isAtomicType()) {
12671 SourceRange SR(LHSExpr->getBeginLoc(), RHSExpr->getEndLoc());
12672 if (BO_Assign == Opc)
12673 Diag(OpLoc, diag::err_opencl_atomic_init) << 0 << SR;
12674 else
12675 ResultTy = InvalidOperands(OpLoc, LHS, RHS);
12676 return ExprError();
12677 }
12678
12679 // OpenCL special types - image, sampler, pipe, and blocks are to be used
12680 // only with a builtin functions and therefore should be disallowed here.
12681 if (LHSTy->isImageType() || RHSTy->isImageType() ||
12682 LHSTy->isSamplerT() || RHSTy->isSamplerT() ||
12683 LHSTy->isPipeType() || RHSTy->isPipeType() ||
12684 LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) {
12685 ResultTy = InvalidOperands(OpLoc, LHS, RHS);
12686 return ExprError();
12687 }
12688 }
12689
12690 // Diagnose operations on the unsupported types for OpenMP device compilation.
12691 if (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice) {
12692 if (Opc != BO_Assign && Opc != BO_Comma) {
12693 checkOpenMPDeviceExpr(LHSExpr);
12694 checkOpenMPDeviceExpr(RHSExpr);
12695 }
12696 }
12697
12698 switch (Opc) {
12699 case BO_Assign:
12700 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType());
12701 if (getLangOpts().CPlusPlus &&
12702 LHS.get()->getObjectKind() != OK_ObjCProperty) {
12703 VK = LHS.get()->getValueKind();
12704 OK = LHS.get()->getObjectKind();
12705 }
12706 if (!ResultTy.isNull()) {
12707 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc, true);
12708 DiagnoseSelfMove(LHS.get(), RHS.get(), OpLoc);
12709
12710 // Avoid copying a block to the heap if the block is assigned to a local
12711 // auto variable that is declared in the same scope as the block. This
12712 // optimization is unsafe if the local variable is declared in an outer
12713 // scope. For example:
12714 //
12715 // BlockTy b;
12716 // {
12717 // b = ^{...};
12718 // }
12719 // // It is unsafe to invoke the block here if it wasn't copied to the
12720 // // heap.
12721 // b();
12722
12723 if (auto *BE = dyn_cast<BlockExpr>(RHS.get()->IgnoreParens()))
12724 if (auto *DRE = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParens()))
12725 if (auto *VD = dyn_cast<VarDecl>(DRE->getDecl()))
12726 if (VD->hasLocalStorage() && getCurScope()->isDeclScope(VD))
12727 BE->getBlockDecl()->setCanAvoidCopyToHeap();
12728 }
12729 RecordModifiableNonNullParam(*this, LHS.get());
12730 break;
12731 case BO_PtrMemD:
12732 case BO_PtrMemI:
12733 ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc,
12734 Opc == BO_PtrMemI);
12735 break;
12736 case BO_Mul:
12737 case BO_Div:
12738 ConvertHalfVec = true;
12739 ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false,
12740 Opc == BO_Div);
12741 break;
12742 case BO_Rem:
12743 ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc);
12744 break;
12745 case BO_Add:
12746 ConvertHalfVec = true;
12747 ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc);
12748 break;
12749 case BO_Sub:
12750 ConvertHalfVec = true;
12751 ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc);
12752 break;
12753 case BO_Shl:
12754 case BO_Shr:
12755 ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc);
12756 break;
12757 case BO_LE:
12758 case BO_LT:
12759 case BO_GE:
12760 case BO_GT:
12761 ConvertHalfVec = true;
12762 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
12763 break;
12764 case BO_EQ:
12765 case BO_NE:
12766 ConvertHalfVec = true;
12767 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
12768 break;
12769 case BO_Cmp:
12770 ConvertHalfVec = true;
12771 ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
12772 assert(ResultTy.isNull() || ResultTy->getAsCXXRecordDecl());
12773 break;
12774 case BO_And:
12775 checkObjCPointerIntrospection(*this, LHS, RHS, OpLoc);
12776 LLVM_FALLTHROUGH;
12777 case BO_Xor:
12778 case BO_Or:
12779 ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, Opc);
12780 break;
12781 case BO_LAnd:
12782 case BO_LOr:
12783 ConvertHalfVec = true;
12784 ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc);
12785 break;
12786 case BO_MulAssign:
12787 case BO_DivAssign:
12788 ConvertHalfVec = true;
12789 CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true,
12790 Opc == BO_DivAssign);
12791 CompLHSTy = CompResultTy;
12792 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12793 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12794 break;
12795 case BO_RemAssign:
12796 CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true);
12797 CompLHSTy = CompResultTy;
12798 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12799 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12800 break;
12801 case BO_AddAssign:
12802 ConvertHalfVec = true;
12803 CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy);
12804 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12805 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12806 break;
12807 case BO_SubAssign:
12808 ConvertHalfVec = true;
12809 CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy);
12810 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12811 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12812 break;
12813 case BO_ShlAssign:
12814 case BO_ShrAssign:
12815 CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true);
12816 CompLHSTy = CompResultTy;
12817 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12818 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12819 break;
12820 case BO_AndAssign:
12821 case BO_OrAssign: // fallthrough
12822 DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc, true);
12823 LLVM_FALLTHROUGH;
12824 case BO_XorAssign:
12825 CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, Opc);
12826 CompLHSTy = CompResultTy;
12827 if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
12828 ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
12829 break;
12830 case BO_Comma:
12831 ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc);
12832 if (getLangOpts().CPlusPlus && !RHS.isInvalid()) {
12833 VK = RHS.get()->getValueKind();
12834 OK = RHS.get()->getObjectKind();
12835 }
12836 break;
12837 }
12838 if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
12839 return ExprError();
12840
12841 // Some of the binary operations require promoting operands of half vector to
12842 // float vectors and truncating the result back to half vector. For now, we do
12843 // this only when HalfArgsAndReturn is set (that is, when the target is arm or
12844 // arm64).
12845 assert(isVector(RHS.get()->getType(), Context.HalfTy) ==
12846 isVector(LHS.get()->getType(), Context.HalfTy) &&
12847 "both sides are half vectors or neither sides are");
12848 ConvertHalfVec = needsConversionOfHalfVec(ConvertHalfVec, Context,
12849 LHS.get()->getType());
12850
12851 // Check for array bounds violations for both sides of the BinaryOperator
12852 CheckArrayAccess(LHS.get());
12853 CheckArrayAccess(RHS.get());
12854
12855 if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(LHS.get()->IgnoreParenCasts())) {
12856 NamedDecl *ObjectSetClass = LookupSingleName(TUScope,
12857 &Context.Idents.get("object_setClass"),
12858 SourceLocation(), LookupOrdinaryName);
12859 if (ObjectSetClass && isa<ObjCIsaExpr>(LHS.get())) {
12860 SourceLocation RHSLocEnd = getLocForEndOfToken(RHS.get()->getEndLoc());
12861 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign)
12862 << FixItHint::CreateInsertion(LHS.get()->getBeginLoc(),
12863 "object_setClass(")
12864 << FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc),
12865 ",")
12866 << FixItHint::CreateInsertion(RHSLocEnd, ")");
12867 }
12868 else
12869 Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
12870 }
12871 else if (const ObjCIvarRefExpr *OIRE =
12872 dyn_cast<ObjCIvarRefExpr>(LHS.get()->IgnoreParenCasts()))
12873 DiagnoseDirectIsaAccess(*this, OIRE, OpLoc, RHS.get());
12874
12875 // Opc is not a compound assignment if CompResultTy is null.
12876 if (CompResultTy.isNull()) {
12877 if (ConvertHalfVec)
12878 return convertHalfVecBinOp(*this, LHS, RHS, Opc, ResultTy, VK, OK, false,
12879 OpLoc, FPFeatures);
12880 return new (Context) BinaryOperator(LHS.get(), RHS.get(), Opc, ResultTy, VK,
12881 OK, OpLoc, FPFeatures);
12882 }
12883
12884 // Handle compound assignments.
12885 if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() !=
12886 OK_ObjCProperty) {
12887 VK = VK_LValue;
12888 OK = LHS.get()->getObjectKind();
12889 }
12890
12891 if (ConvertHalfVec)
12892 return convertHalfVecBinOp(*this, LHS, RHS, Opc, ResultTy, VK, OK, true,
12893 OpLoc, FPFeatures);
12894
12895 return new (Context) CompoundAssignOperator(
12896 LHS.get(), RHS.get(), Opc, ResultTy, VK, OK, CompLHSTy, CompResultTy,
12897 OpLoc, FPFeatures);
12898}
12899
12900/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison
12901/// operators are mixed in a way that suggests that the programmer forgot that
12902/// comparison operators have higher precedence. The most typical example of
12903/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1".
12904static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc,
12905 SourceLocation OpLoc, Expr *LHSExpr,
12906 Expr *RHSExpr) {
12907 BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(LHSExpr);
12908 BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(RHSExpr);
12909
12910 // Check that one of the sides is a comparison operator and the other isn't.
12911 bool isLeftComp = LHSBO && LHSBO->isComparisonOp();
12912 bool isRightComp = RHSBO && RHSBO->isComparisonOp();
12913 if (isLeftComp == isRightComp)
12914 return;
12915
12916 // Bitwise operations are sometimes used as eager logical ops.
12917 // Don't diagnose this.
12918 bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp();
12919 bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp();
12920 if (isLeftBitwise || isRightBitwise)
12921 return;
12922
12923 SourceRange DiagRange = isLeftComp
12924 ? SourceRange(LHSExpr->getBeginLoc(), OpLoc)
12925 : SourceRange(OpLoc, RHSExpr->getEndLoc());
12926 StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr();
12927 SourceRange ParensRange =
12928 isLeftComp
12929 ? SourceRange(LHSBO->getRHS()->getBeginLoc(), RHSExpr->getEndLoc())
12930 : SourceRange(LHSExpr->getBeginLoc(), RHSBO->getLHS()->getEndLoc());
12931
12932 Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel)
12933 << DiagRange << BinaryOperator::getOpcodeStr(Opc) << OpStr;
12934 SuggestParentheses(Self, OpLoc,
12935 Self.PDiag(diag::note_precedence_silence) << OpStr,
12936 (isLeftComp ? LHSExpr : RHSExpr)->getSourceRange());
12937 SuggestParentheses(Self, OpLoc,
12938 Self.PDiag(diag::note_precedence_bitwise_first)
12939 << BinaryOperator::getOpcodeStr(Opc),
12940 ParensRange);
12941}
12942
12943/// It accepts a '&&' expr that is inside a '||' one.
12944/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression
12945/// in parentheses.
12946static void
12947EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc,
12948 BinaryOperator *Bop) {
12949 assert(Bop->getOpcode() == BO_LAnd);
12950 Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or)
12951 << Bop->getSourceRange() << OpLoc;
12952 SuggestParentheses(Self, Bop->getOperatorLoc(),
12953 Self.PDiag(diag::note_precedence_silence)
12954 << Bop->getOpcodeStr(),
12955 Bop->getSourceRange());
12956}
12957
12958/// Returns true if the given expression can be evaluated as a constant
12959/// 'true'.
12960static bool EvaluatesAsTrue(Sema &S, Expr *E) {
12961 bool Res;
12962 return !E->isValueDependent() &&
12963 E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res;
12964}
12965
12966/// Returns true if the given expression can be evaluated as a constant
12967/// 'false'.
12968static bool EvaluatesAsFalse(Sema &S, Expr *E) {
12969 bool Res;
12970 return !E->isValueDependent() &&
12971 E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res;
12972}
12973
12974/// Look for '&&' in the left hand of a '||' expr.
12975static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
12976 Expr *LHSExpr, Expr *RHSExpr) {
12977 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) {
12978 if (Bop->getOpcode() == BO_LAnd) {
12979 // If it's "a && b || 0" don't warn since the precedence doesn't matter.
12980 if (EvaluatesAsFalse(S, RHSExpr))
12981 return;
12982 // If it's "1 && a || b" don't warn since the precedence doesn't matter.
12983 if (!EvaluatesAsTrue(S, Bop->getLHS()))
12984 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
12985 } else if (Bop->getOpcode() == BO_LOr) {
12986 if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) {
12987 // If it's "a || b && 1 || c" we didn't warn earlier for
12988 // "a || b && 1", but warn now.
12989 if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS()))
12990 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop);
12991 }
12992 }
12993 }
12994}
12995
12996/// Look for '&&' in the right hand of a '||' expr.
12997static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc,
12998 Expr *LHSExpr, Expr *RHSExpr) {
12999 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) {
13000 if (Bop->getOpcode() == BO_LAnd) {
13001 // If it's "0 || a && b" don't warn since the precedence doesn't matter.
13002 if (EvaluatesAsFalse(S, LHSExpr))
13003 return;
13004 // If it's "a || b && 1" don't warn since the precedence doesn't matter.
13005 if (!EvaluatesAsTrue(S, Bop->getRHS()))
13006 return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
13007 }
13008 }
13009}
13010
13011/// Look for bitwise op in the left or right hand of a bitwise op with
13012/// lower precedence and emit a diagnostic together with a fixit hint that wraps
13013/// the '&' expression in parentheses.
13014static void DiagnoseBitwiseOpInBitwiseOp(Sema &S, BinaryOperatorKind Opc,
13015 SourceLocation OpLoc, Expr *SubExpr) {
13016 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
13017 if (Bop->isBitwiseOp() && Bop->getOpcode() < Opc) {
13018 S.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_op_in_bitwise_op)
13019 << Bop->getOpcodeStr() << BinaryOperator::getOpcodeStr(Opc)
13020 << Bop->getSourceRange() << OpLoc;
13021 SuggestParentheses(S, Bop->getOperatorLoc(),
13022 S.PDiag(diag::note_precedence_silence)
13023 << Bop->getOpcodeStr(),
13024 Bop->getSourceRange());
13025 }
13026 }
13027}
13028
13029static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc,
13030 Expr *SubExpr, StringRef Shift) {
13031 if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
13032 if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) {
13033 StringRef Op = Bop->getOpcodeStr();
13034 S.Diag(Bop->getOperatorLoc(), diag::warn_addition_in_bitshift)
13035 << Bop->getSourceRange() << OpLoc << Shift << Op;
13036 SuggestParentheses(S, Bop->getOperatorLoc(),
13037 S.PDiag(diag::note_precedence_silence) << Op,
13038 Bop->getSourceRange());
13039 }
13040 }
13041}
13042
13043static void DiagnoseShiftCompare(Sema &S, SourceLocation OpLoc,
13044 Expr *LHSExpr, Expr *RHSExpr) {
13045 CXXOperatorCallExpr *OCE = dyn_cast<CXXOperatorCallExpr>(LHSExpr);
13046 if (!OCE)
13047 return;
13048
13049 FunctionDecl *FD = OCE->getDirectCallee();
13050 if (!FD || !FD->isOverloadedOperator())
13051 return;
13052
13053 OverloadedOperatorKind Kind = FD->getOverloadedOperator();
13054 if (Kind != OO_LessLess && Kind != OO_GreaterGreater)
13055 return;
13056
13057 S.Diag(OpLoc, diag::warn_overloaded_shift_in_comparison)
13058 << LHSExpr->getSourceRange() << RHSExpr->getSourceRange()
13059 << (Kind == OO_LessLess);
13060 SuggestParentheses(S, OCE->getOperatorLoc(),
13061 S.PDiag(diag::note_precedence_silence)
13062 << (Kind == OO_LessLess ? "<<" : ">>"),
13063 OCE->getSourceRange());
13064 SuggestParentheses(
13065 S, OpLoc, S.PDiag(diag::note_evaluate_comparison_first),
13066 SourceRange(OCE->getArg(1)->getBeginLoc(), RHSExpr->getEndLoc()));
13067}
13068
13069/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky
13070/// precedence.
13071static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc,
13072 SourceLocation OpLoc, Expr *LHSExpr,
13073 Expr *RHSExpr){
13074 // Diagnose "arg1 'bitwise' arg2 'eq' arg3".
13075 if (BinaryOperator::isBitwiseOp(Opc))
13076 DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr);
13077
13078 // Diagnose "arg1 & arg2 | arg3"
13079 if ((Opc == BO_Or || Opc == BO_Xor) &&
13080 !OpLoc.isMacroID()/* Don't warn in macros. */) {
13081 DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, LHSExpr);
13082 DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, RHSExpr);
13083 }
13084
13085 // Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
13086 // We don't warn for 'assert(a || b && "bad")' since this is safe.
13087 if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
13088 DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr);
13089 DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr);
13090 }
13091
13092 if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Self.getASTContext()))
13093 || Opc == BO_Shr) {
13094 StringRef Shift = BinaryOperator::getOpcodeStr(Opc);
13095 DiagnoseAdditionInShift(Self, OpLoc, LHSExpr, Shift);
13096 DiagnoseAdditionInShift(Self, OpLoc, RHSExpr, Shift);
13097 }
13098
13099 // Warn on overloaded shift operators and comparisons, such as:
13100 // cout << 5 == 4;
13101 if (BinaryOperator::isComparisonOp(Opc))
13102 DiagnoseShiftCompare(Self, OpLoc, LHSExpr, RHSExpr);
13103}
13104
13105// Binary Operators. 'Tok' is the token for the operator.
13106ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc,
13107 tok::TokenKind Kind,
13108 Expr *LHSExpr, Expr *RHSExpr) {
13109 BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind);
13110 assert(LHSExpr && "ActOnBinOp(): missing left expression");
13111 assert(RHSExpr && "ActOnBinOp(): missing right expression");
13112
13113 // Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0"
13114 DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr);
13115
13116 return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr);
13117}
13118
13119/// Build an overloaded binary operator expression in the given scope.
13120static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc,
13121 BinaryOperatorKind Opc,
13122 Expr *LHS, Expr *RHS) {
13123 switch (Opc) {
13124 case BO_Assign:
13125 case BO_DivAssign:
13126 case BO_RemAssign:
13127 case BO_SubAssign:
13128 case BO_AndAssign:
13129 case BO_OrAssign:
13130 case BO_XorAssign:
13131 DiagnoseSelfAssignment(S, LHS, RHS, OpLoc, false);
13132 CheckIdentityFieldAssignment(LHS, RHS, OpLoc, S);
13133 break;
13134 default:
13135 break;
13136 }
13137
13138 // Find all of the overloaded operators visible from this
13139 // point. We perform both an operator-name lookup from the local
13140 // scope and an argument-dependent lookup based on the types of
13141 // the arguments.
13142 UnresolvedSet<16> Functions;
13143 OverloadedOperatorKind OverOp
13144 = BinaryOperator::getOverloadedOperator(Opc);
13145 if (Sc && OverOp != OO_None && OverOp != OO_Equal)
13146 S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(),
13147 RHS->getType(), Functions);
13148
13149 // Build the (potentially-overloaded, potentially-dependent)
13150 // binary operation.
13151 return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS);
13152}
13153
13154ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
13155 BinaryOperatorKind Opc,
13156 Expr *LHSExpr, Expr *RHSExpr) {
13157 ExprResult LHS, RHS;
13158 std::tie(LHS, RHS) = CorrectDelayedTyposInBinOp(*this, Opc, LHSExpr, RHSExpr);
13159 if (!LHS.isUsable() || !RHS.isUsable())
13160 return ExprError();
13161 LHSExpr = LHS.get();
13162 RHSExpr = RHS.get();
13163
13164 // We want to end up calling one of checkPseudoObjectAssignment
13165 // (if the LHS is a pseudo-object), BuildOverloadedBinOp (if
13166 // both expressions are overloadable or either is type-dependent),
13167 // or CreateBuiltinBinOp (in any other case). We also want to get
13168 // any placeholder types out of the way.
13169
13170 // Handle pseudo-objects in the LHS.
13171 if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) {
13172 // Assignments with a pseudo-object l-value need special analysis.
13173 if (pty->getKind() == BuiltinType::PseudoObject &&
13174 BinaryOperator::isAssignmentOp(Opc))
13175 return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr);
13176
13177 // Don't resolve overloads if the other type is overloadable.
13178 if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload) {
13179 // We can't actually test that if we still have a placeholder,
13180 // though. Fortunately, none of the exceptions we see in that
13181 // code below are valid when the LHS is an overload set. Note
13182 // that an overload set can be dependently-typed, but it never
13183 // instantiates to having an overloadable type.
13184 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
13185 if (resolvedRHS.isInvalid()) return ExprError();
13186 RHSExpr = resolvedRHS.get();
13187
13188 if (RHSExpr->isTypeDependent() ||
13189 RHSExpr->getType()->isOverloadableType())
13190 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
13191 }
13192
13193 // If we're instantiating "a.x < b" or "A::x < b" and 'x' names a function
13194 // template, diagnose the missing 'template' keyword instead of diagnosing
13195 // an invalid use of a bound member function.
13196 //
13197 // Note that "A::x < b" might be valid if 'b' has an overloadable type due
13198 // to C++1z [over.over]/1.4, but we already checked for that case above.
13199 if (Opc == BO_LT && inTemplateInstantiation() &&
13200 (pty->getKind() == BuiltinType::BoundMember ||
13201 pty->getKind() == BuiltinType::Overload)) {
13202 auto *OE = dyn_cast<OverloadExpr>(LHSExpr);
13203 if (OE && !OE->hasTemplateKeyword() && !OE->hasExplicitTemplateArgs() &&
13204 std::any_of(OE->decls_begin(), OE->decls_end(), [](NamedDecl *ND) {
13205 return isa<FunctionTemplateDecl>(ND);
13206 })) {
13207 Diag(OE->getQualifier() ? OE->getQualifierLoc().getBeginLoc()
13208 : OE->getNameLoc(),
13209 diag::err_template_kw_missing)
13210 << OE->getName().getAsString() << "";
13211 return ExprError();
13212 }
13213 }
13214
13215 ExprResult LHS = CheckPlaceholderExpr(LHSExpr);
13216 if (LHS.isInvalid()) return ExprError();
13217 LHSExpr = LHS.get();
13218 }
13219
13220 // Handle pseudo-objects in the RHS.
13221 if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) {
13222 // An overload in the RHS can potentially be resolved by the type
13223 // being assigned to.
13224 if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) {
13225 if (getLangOpts().CPlusPlus &&
13226 (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent() ||
13227 LHSExpr->getType()->isOverloadableType()))
13228 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
13229
13230 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
13231 }
13232
13233 // Don't resolve overloads if the other type is overloadable.
13234 if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload &&
13235 LHSExpr->getType()->isOverloadableType())
13236 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
13237
13238 ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
13239 if (!resolvedRHS.isUsable()) return ExprError();
13240 RHSExpr = resolvedRHS.get();
13241 }
13242
13243 if (getLangOpts().CPlusPlus) {
13244 // If either expression is type-dependent, always build an
13245 // overloaded op.
13246 if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())
13247 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
13248
13249 // Otherwise, build an overloaded op if either expression has an
13250 // overloadable type.
13251 if (LHSExpr->getType()->isOverloadableType() ||
13252 RHSExpr->getType()->isOverloadableType())
13253 return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
13254 }
13255
13256 // Build a built-in binary operation.
13257 return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
13258}
13259
13260static bool isOverflowingIntegerType(ASTContext &Ctx, QualType T) {
13261 if (T.isNull() || T->isDependentType())
13262 return false;
13263
13264 if (!T->isPromotableIntegerType())
13265 return true;
13266
13267 return Ctx.getIntWidth(T) >= Ctx.getIntWidth(Ctx.IntTy);
13268}
13269
13270ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
13271 UnaryOperatorKind Opc,
13272 Expr *InputExpr) {
13273 if (InputExpr->getType().getQualifiers().hasOutput()) {
13274 return ExprError(Diag(InputExpr->getExprLoc(), diag::err_typecheck_read_output)
13275 << InputExpr->getSourceRange());
13276 }
13277
13278
13279 ExprResult Input = InputExpr;
13280 ExprValueKind VK = VK_RValue;
13281 ExprObjectKind OK = OK_Ordinary;
13282 QualType resultType;
13283 bool CanOverflow = false;
13284
13285 bool ConvertHalfVec = false;
13286 if (getLangOpts().OpenCL) {
13287 QualType Ty = InputExpr->getType();
13288 // The only legal unary operation for atomics is '&'.
13289 if ((Opc != UO_AddrOf && Ty->isAtomicType()) ||
13290 // OpenCL special types - image, sampler, pipe, and blocks are to be used
13291 // only with a builtin functions and therefore should be disallowed here.
13292 (Ty->isImageType() || Ty->isSamplerT() || Ty->isPipeType()
13293 || Ty->isBlockPointerType())) {
13294 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13295 << InputExpr->getType()
13296 << Input.get()->getSourceRange());
13297 }
13298 }
13299 // Diagnose operations on the unsupported types for OpenMP device compilation.
13300 if (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice) {
13301 if (UnaryOperator::isIncrementDecrementOp(Opc) ||
13302 UnaryOperator::isArithmeticOp(Opc))
13303 checkOpenMPDeviceExpr(InputExpr);
13304 }
13305
13306 switch (Opc) {
13307 case UO_PreInc:
13308 case UO_PreDec:
13309 case UO_PostInc:
13310 case UO_PostDec:
13311 resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OK,
13312 OpLoc,
13313 Opc == UO_PreInc ||
13314 Opc == UO_PostInc,
13315 Opc == UO_PreInc ||
13316 Opc == UO_PreDec);
13317 CanOverflow = isOverflowingIntegerType(Context, resultType);
13318 break;
13319 case UO_AddrOf:
13320 resultType = CheckAddressOfOperand(Input, OpLoc);
13321 CheckAddressOfNoDeref(InputExpr);
13322 RecordModifiableNonNullParam(*this, InputExpr);
13323 break;
13324 case UO_Deref: {
13325 Input = DefaultFunctionArrayLvalueConversion(Input.get());
13326 if (Input.isInvalid()) return ExprError();
13327 resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc);
13328 break;
13329 }
13330 case UO_Plus:
13331 case UO_Minus:
13332 CanOverflow = Opc == UO_Minus &&
13333 isOverflowingIntegerType(Context, Input.get()->getType());
13334 Input = UsualUnaryConversions(Input.get());
13335 if (Input.isInvalid()) return ExprError();
13336 // Unary plus and minus require promoting an operand of half vector to a
13337 // float vector and truncating the result back to a half vector. For now, we
13338 // do this only when HalfArgsAndReturns is set (that is, when the target is
13339 // arm or arm64).
13340 ConvertHalfVec =
13341 needsConversionOfHalfVec(true, Context, Input.get()->getType());
13342
13343 // If the operand is a half vector, promote it to a float vector.
13344 if (ConvertHalfVec)
13345 Input = convertVector(Input.get(), Context.FloatTy, *this);
13346 resultType = Input.get()->getType();
13347 if (resultType->isDependentType())
13348 break;
13349 if (resultType->isArithmeticType()) // C99 6.5.3.3p1
13350 break;
13351 else if (resultType->isVectorType() &&
13352 // The z vector extensions don't allow + or - with bool vectors.
13353 (!Context.getLangOpts().ZVector ||
13354 resultType->getAs<VectorType>()->getVectorKind() !=
13355 VectorType::AltiVecBool))
13356 break;
13357 else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6
13358 Opc == UO_Plus &&
13359 resultType->isPointerType())
13360 break;
13361
13362 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13363 << resultType << Input.get()->getSourceRange());
13364
13365 case UO_Not: // bitwise complement
13366 Input = UsualUnaryConversions(Input.get());
13367 if (Input.isInvalid())
13368 return ExprError();
13369 resultType = Input.get()->getType();
13370
13371 if (resultType->isDependentType())
13372 break;
13373 // C99 6.5.3.3p1. We allow complex int and float as a GCC extension.
13374 if (resultType->isComplexType() || resultType->isComplexIntegerType())
13375 // C99 does not support '~' for complex conjugation.
13376 Diag(OpLoc, diag::ext_integer_complement_complex)
13377 << resultType << Input.get()->getSourceRange();
13378 else if (resultType->hasIntegerRepresentation())
13379 break;
13380 else if (resultType->isExtVectorType() && Context.getLangOpts().OpenCL) {
13381 // OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate
13382 // on vector float types.
13383 QualType T = resultType->getAs<ExtVectorType>()->getElementType();
13384 if (!T->isIntegerType())
13385 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13386 << resultType << Input.get()->getSourceRange());
13387 } else {
13388 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13389 << resultType << Input.get()->getSourceRange());
13390 }
13391 break;
13392
13393 case UO_LNot: // logical negation
13394 // Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
13395 Input = DefaultFunctionArrayLvalueConversion(Input.get());
13396 if (Input.isInvalid()) return ExprError();
13397 resultType = Input.get()->getType();
13398
13399 // Though we still have to promote half FP to float...
13400 if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) {
13401 Input = ImpCastExprToType(Input.get(), Context.FloatTy, CK_FloatingCast).get();
13402 resultType = Context.FloatTy;
13403 }
13404
13405 if (resultType->isDependentType())
13406 break;
13407 if (resultType->isScalarType() && !isScopedEnumerationType(resultType)) {
13408 // C99 6.5.3.3p1: ok, fallthrough;
13409 if (Context.getLangOpts().CPlusPlus) {
13410 // C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9:
13411 // operand contextually converted to bool.
13412 Input = ImpCastExprToType(Input.get(), Context.BoolTy,
13413 ScalarTypeToBooleanCastKind(resultType));
13414 } else if (Context.getLangOpts().OpenCL &&
13415 Context.getLangOpts().OpenCLVersion < 120) {
13416 // OpenCL v1.1 6.3.h: The logical operator not (!) does not
13417 // operate on scalar float types.
13418 if (!resultType->isIntegerType() && !resultType->isPointerType())
13419 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13420 << resultType << Input.get()->getSourceRange());
13421 }
13422 } else if (resultType->isExtVectorType()) {
13423 if (Context.getLangOpts().OpenCL &&
13424 Context.getLangOpts().OpenCLVersion < 120 &&
13425 !Context.getLangOpts().OpenCLCPlusPlus) {
13426 // OpenCL v1.1 6.3.h: The logical operator not (!) does not
13427 // operate on vector float types.
13428 QualType T = resultType->getAs<ExtVectorType>()->getElementType();
13429 if (!T->isIntegerType())
13430 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13431 << resultType << Input.get()->getSourceRange());
13432 }
13433 // Vector logical not returns the signed variant of the operand type.
13434 resultType = GetSignedVectorType(resultType);
13435 break;
13436 } else {
13437 // FIXME: GCC's vector extension permits the usage of '!' with a vector
13438 // type in C++. We should allow that here too.
13439 return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
13440 << resultType << Input.get()->getSourceRange());
13441 }
13442
13443 // LNot always has type int. C99 6.5.3.3p5.
13444 // In C++, it's bool. C++ 5.3.1p8
13445 resultType = Context.getLogicalOperationType();
13446 break;
13447 case UO_Real:
13448 case UO_Imag:
13449 resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real);
13450 // _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary
13451 // complex l-values to ordinary l-values and all other values to r-values.
13452 if (Input.isInvalid()) return ExprError();
13453 if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) {
13454 if (Input.get()->getValueKind() != VK_RValue &&
13455 Input.get()->getObjectKind() == OK_Ordinary)
13456 VK = Input.get()->getValueKind();
13457 } else if (!getLangOpts().CPlusPlus) {
13458 // In C, a volatile scalar is read by __imag. In C++, it is not.
13459 Input = DefaultLvalueConversion(Input.get());
13460 }
13461 break;
13462 case UO_Extension:
13463 resultType = Input.get()->getType();
13464 VK = Input.get()->getValueKind();
13465 OK = Input.get()->getObjectKind();
13466 break;
13467 case UO_Coawait:
13468 // It's unnecessary to represent the pass-through operator co_await in the
13469 // AST; just return the input expression instead.
13470 assert(!Input.get()->getType()->isDependentType() &&
13471 "the co_await expression must be non-dependant before "
13472 "building operator co_await");
13473 return Input;
13474 }
13475 if (resultType.isNull() || Input.isInvalid())
13476 return ExprError();
13477
13478 // Check for array bounds violations in the operand of the UnaryOperator,
13479 // except for the '*' and '&' operators that have to be handled specially
13480 // by CheckArrayAccess (as there are special cases like &array[arraysize]
13481 // that are explicitly defined as valid by the standard).
13482 if (Opc != UO_AddrOf && Opc != UO_Deref)
13483 CheckArrayAccess(Input.get());
13484
13485 auto *UO = new (Context)
13486 UnaryOperator(Input.get(), Opc, resultType, VK, OK, OpLoc, CanOverflow);
13487
13488 if (Opc == UO_Deref && UO->getType()->hasAttr(attr::NoDeref) &&
13489 !isa<ArrayType>(UO->getType().getDesugaredType(Context)))
13490 ExprEvalContexts.back().PossibleDerefs.insert(UO);
13491
13492 // Convert the result back to a half vector.
13493 if (ConvertHalfVec)
13494 return convertVector(UO, Context.HalfTy, *this);
13495 return UO;
13496}
13497
13498/// Determine whether the given expression is a qualified member
13499/// access expression, of a form that could be turned into a pointer to member
13500/// with the address-of operator.
13501bool Sema::isQualifiedMemberAccess(Expr *E) {
13502 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
13503 if (!DRE->getQualifier())
13504 return false;
13505
13506 ValueDecl *VD = DRE->getDecl();
13507 if (!VD->isCXXClassMember())
13508 return false;
13509
13510 if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD))
13511 return true;
13512 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD))
13513 return Method->isInstance();
13514
13515 return false;
13516 }
13517
13518 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {
13519 if (!ULE->getQualifier())
13520 return false;
13521
13522 for (NamedDecl *D : ULE->decls()) {
13523 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
13524 if (Method->isInstance())
13525 return true;
13526 } else {
13527 // Overload set does not contain methods.
13528 break;
13529 }
13530 }
13531
13532 return false;
13533 }
13534
13535 return false;
13536}
13537
13538ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc,
13539 UnaryOperatorKind Opc, Expr *Input) {
13540 // First things first: handle placeholders so that the
13541 // overloaded-operator check considers the right type.
13542 if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) {
13543 // Increment and decrement of pseudo-object references.
13544 if (pty->getKind() == BuiltinType::PseudoObject &&
13545 UnaryOperator::isIncrementDecrementOp(Opc))
13546 return checkPseudoObjectIncDec(S, OpLoc, Opc, Input);
13547
13548 // extension is always a builtin operator.
13549 if (Opc == UO_Extension)
13550 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
13551
13552 // & gets special logic for several kinds of placeholder.
13553 // The builtin code knows what to do.
13554 if (Opc == UO_AddrOf &&
13555 (pty->getKind() == BuiltinType::Overload ||
13556 pty->getKind() == BuiltinType::UnknownAny ||
13557 pty->getKind() == BuiltinType::BoundMember))
13558 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
13559
13560 // Anything else needs to be handled now.
13561 ExprResult Result = CheckPlaceholderExpr(Input);
13562 if (Result.isInvalid()) return ExprError();
13563 Input = Result.get();
13564 }
13565
13566 if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() &&
13567 UnaryOperator::getOverloadedOperator(Opc) != OO_None &&
13568 !(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) {
13569 // Find all of the overloaded operators visible from this
13570 // point. We perform both an operator-name lookup from the local
13571 // scope and an argument-dependent lookup based on the types of
13572 // the arguments.
13573 UnresolvedSet<16> Functions;
13574 OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc);
13575 if (S && OverOp != OO_None)
13576 LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(),
13577 Functions);
13578
13579 return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input);
13580 }
13581
13582 return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
13583}
13584
13585// Unary Operators. 'Tok' is the token for the operator.
13586ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
13587 tok::TokenKind Op, Expr *Input) {
13588 return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input);
13589}
13590
13591/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
13592ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
13593 LabelDecl *TheDecl) {
13594 TheDecl->markUsed(Context);
13595 // Create the AST node. The address of a label always has type 'void*'.
13596 return new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl,
13597 Context.getPointerType(Context.VoidTy));
13598}
13599
13600void Sema::ActOnStartStmtExpr() {
13601 PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
13602}
13603
13604void Sema::ActOnStmtExprError() {
13605 // Note that function is also called by TreeTransform when leaving a
13606 // StmtExpr scope without rebuilding anything.
13607
13608 DiscardCleanupsInEvaluationContext();
13609 PopExpressionEvaluationContext();
13610}
13611
13612ExprResult
13613Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
13614 SourceLocation RPLoc) { // "({..})"
13615 assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
13616 CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
13617
13618 if (hasAnyUnrecoverableErrorsInThisFunction())
13619 DiscardCleanupsInEvaluationContext();
13620 assert(!Cleanup.exprNeedsCleanups() &&
13621 "cleanups within StmtExpr not correctly bound!");
13622 PopExpressionEvaluationContext();
13623
13624 // FIXME: there are a variety of strange constraints to enforce here, for
13625 // example, it is not possible to goto into a stmt expression apparently.
13626 // More semantic analysis is needed.
13627
13628 // If there are sub-stmts in the compound stmt, take the type of the last one
13629 // as the type of the stmtexpr.
13630 QualType Ty = Context.VoidTy;
13631 bool StmtExprMayBindToTemp = false;
13632 if (!Compound->body_empty()) {
13633 if (const auto *LastStmt = dyn_cast<ValueStmt>(Compound->body_back())) {
13634 if (const Expr *Value = LastStmt->getExprStmt()) {
13635 StmtExprMayBindToTemp = true;
13636 Ty = Value->getType();
13637 }
13638 }
13639 }
13640
13641 // FIXME: Check that expression type is complete/non-abstract; statement
13642 // expressions are not lvalues.
13643 Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc);
13644 if (StmtExprMayBindToTemp)
13645 return MaybeBindToTemporary(ResStmtExpr);
13646 return ResStmtExpr;
13647}
13648
13649ExprResult Sema::ActOnStmtExprResult(ExprResult ER) {
13650 if (ER.isInvalid())
13651 return ExprError();
13652
13653 // Do function/array conversion on the last expression, but not
13654 // lvalue-to-rvalue. However, initialize an unqualified type.
13655 ER = DefaultFunctionArrayConversion(ER.get());
13656 if (ER.isInvalid())
13657 return ExprError();
13658 Expr *E = ER.get();
13659
13660 if (E->isTypeDependent())
13661 return E;
13662
13663 // In ARC, if the final expression ends in a consume, splice
13664 // the consume out and bind it later. In the alternate case
13665 // (when dealing with a retainable type), the result
13666 // initialization will create a produce. In both cases the
13667 // result will be +1, and we'll need to balance that out with
13668 // a bind.
13669 auto *Cast = dyn_cast<ImplicitCastExpr>(E);
13670 if (Cast && Cast->getCastKind() == CK_ARCConsumeObject)
13671 return Cast->getSubExpr();
13672
13673 // FIXME: Provide a better location for the initialization.
13674 return PerformCopyInitialization(
13675 InitializedEntity::InitializeStmtExprResult(
13676 E->getBeginLoc(), E->getType().getUnqualifiedType()),
13677 SourceLocation(), E);
13678}
13679
13680ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
13681 TypeSourceInfo *TInfo,
13682 ArrayRef<OffsetOfComponent> Components,
13683 SourceLocation RParenLoc) {
13684 QualType ArgTy = TInfo->getType();
13685 bool Dependent = ArgTy->isDependentType();
13686 SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange();
13687
13688 // We must have at least one component that refers to the type, and the first
13689 // one is known to be a field designator. Verify that the ArgTy represents
13690 // a struct/union/class.
13691 if (!Dependent && !ArgTy->isRecordType())
13692 return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type)
13693 << ArgTy << TypeRange);
13694
13695 // Type must be complete per C99 7.17p3 because a declaring a variable
13696 // with an incomplete type would be ill-formed.
13697 if (!Dependent
13698 && RequireCompleteType(BuiltinLoc, ArgTy,
13699 diag::err_offsetof_incomplete_type, TypeRange))
13700 return ExprError();
13701
13702 bool DidWarnAboutNonPOD = false;
13703 QualType CurrentType = ArgTy;
13704 SmallVector<OffsetOfNode, 4> Comps;
13705 SmallVector<Expr*, 4> Exprs;
13706 for (const OffsetOfComponent &OC : Components) {
13707 if (OC.isBrackets) {
13708 // Offset of an array sub-field. TODO: Should we allow vector elements?
13709 if (!CurrentType->isDependentType()) {
13710 const ArrayType *AT = Context.getAsArrayType(CurrentType);
13711 if(!AT)
13712 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type)
13713 << CurrentType);
13714 CurrentType = AT->getElementType();
13715 } else
13716 CurrentType = Context.DependentTy;
13717
13718 ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E));
13719 if (IdxRval.isInvalid())
13720 return ExprError();
13721 Expr *Idx = IdxRval.get();
13722
13723 // The expression must be an integral expression.
13724 // FIXME: An integral constant expression?
13725 if (!Idx->isTypeDependent() && !Idx->isValueDependent() &&
13726 !Idx->getType()->isIntegerType())
13727 return ExprError(
13728 Diag(Idx->getBeginLoc(), diag::err_typecheck_subscript_not_integer)
13729 << Idx->getSourceRange());
13730
13731 // Record this array index.
13732 Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd));
13733 Exprs.push_back(Idx);
13734 continue;
13735 }
13736
13737 // Offset of a field.
13738 if (CurrentType->isDependentType()) {
13739 // We have the offset of a field, but we can't look into the dependent
13740 // type. Just record the identifier of the field.
13741 Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd));
13742 CurrentType = Context.DependentTy;
13743 continue;
13744 }
13745
13746 // We need to have a complete type to look into.
13747 if (RequireCompleteType(OC.LocStart, CurrentType,
13748 diag::err_offsetof_incomplete_type))
13749 return ExprError();
13750
13751 // Look for the designated field.
13752 const RecordType *RC = CurrentType->getAs<RecordType>();
13753 if (!RC)
13754 return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type)
13755 << CurrentType);
13756 RecordDecl *RD = RC->getDecl();
13757
13758 // C++ [lib.support.types]p5:
13759 // The macro offsetof accepts a restricted set of type arguments in this
13760 // International Standard. type shall be a POD structure or a POD union
13761 // (clause 9).
13762 // C++11 [support.types]p4:
13763 // If type is not a standard-layout class (Clause 9), the results are
13764 // undefined.
13765 if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
13766 bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD();
13767 unsigned DiagID =
13768 LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type
13769 : diag::ext_offsetof_non_pod_type;
13770
13771 if (!IsSafe && !DidWarnAboutNonPOD &&
13772 DiagRuntimeBehavior(BuiltinLoc, nullptr,
13773 PDiag(DiagID)
13774 << SourceRange(Components[0].LocStart, OC.LocEnd)
13775 << CurrentType))
13776 DidWarnAboutNonPOD = true;
13777 }
13778
13779 // Look for the field.
13780 LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName);
13781 LookupQualifiedName(R, RD);
13782 FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>();
13783 IndirectFieldDecl *IndirectMemberDecl = nullptr;
13784 if (!MemberDecl) {
13785 if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>()))
13786 MemberDecl = IndirectMemberDecl->getAnonField();
13787 }
13788
13789 if (!MemberDecl)
13790 return ExprError(Diag(BuiltinLoc, diag::err_no_member)
13791 << OC.U.IdentInfo << RD << SourceRange(OC.LocStart,
13792 OC.LocEnd));
13793
13794 // C99 7.17p3:
13795 // (If the specified member is a bit-field, the behavior is undefined.)
13796 //
13797 // We diagnose this as an error.
13798 if (MemberDecl->isBitField()) {
13799 Diag(OC.LocEnd, diag::err_offsetof_bitfield)
13800 << MemberDecl->getDeclName()
13801 << SourceRange(BuiltinLoc, RParenLoc);
13802 Diag(MemberDecl->getLocation(), diag::note_bitfield_decl);
13803 return ExprError();
13804 }
13805
13806 RecordDecl *Parent = MemberDecl->getParent();
13807 if (IndirectMemberDecl)
13808 Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext());
13809
13810 // If the member was found in a base class, introduce OffsetOfNodes for
13811 // the base class indirections.
13812 CXXBasePaths Paths;
13813 if (IsDerivedFrom(OC.LocStart, CurrentType, Context.getTypeDeclType(Parent),
13814 Paths)) {
13815 if (Paths.getDetectedVirtual()) {
13816 Diag(OC.LocEnd, diag::err_offsetof_field_of_virtual_base)
13817 << MemberDecl->getDeclName()
13818 << SourceRange(BuiltinLoc, RParenLoc);
13819 return ExprError();
13820 }
13821
13822 CXXBasePath &Path = Paths.front();
13823 for (const CXXBasePathElement &B : Path)
13824 Comps.push_back(OffsetOfNode(B.Base));
13825 }
13826
13827 if (IndirectMemberDecl) {
13828 for (auto *FI : IndirectMemberDecl->chain()) {
13829 assert(isa<FieldDecl>(FI));
13830 Comps.push_back(OffsetOfNode(OC.LocStart,
13831 cast<FieldDecl>(FI), OC.LocEnd));
13832 }
13833 } else
13834 Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd));
13835
13836 CurrentType = MemberDecl->getType().getNonReferenceType();
13837 }
13838
13839 return OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, TInfo,
13840 Comps, Exprs, RParenLoc);
13841}
13842
13843ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
13844 SourceLocation BuiltinLoc,
13845 SourceLocation TypeLoc,
13846 ParsedType ParsedArgTy,
13847 ArrayRef<OffsetOfComponent> Components,
13848 SourceLocation RParenLoc) {
13849
13850 TypeSourceInfo *ArgTInfo;
13851 QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo);
13852 if (ArgTy.isNull())
13853 return ExprError();
13854
13855 if (!ArgTInfo)
13856 ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc);
13857
13858 return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, Components, RParenLoc);
13859}
13860
13861
13862ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
13863 Expr *CondExpr,
13864 Expr *LHSExpr, Expr *RHSExpr,
13865 SourceLocation RPLoc) {
13866 assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
13867
13868 ExprValueKind VK = VK_RValue;
13869 ExprObjectKind OK = OK_Ordinary;
13870 QualType resType;
13871 bool ValueDependent = false;
13872 bool CondIsTrue = false;
13873 if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
13874 resType = Context.DependentTy;
13875 ValueDependent = true;
13876 } else {
13877 // The conditional expression is required to be a constant expression.
13878 llvm::APSInt condEval(32);
13879 ExprResult CondICE
13880 = VerifyIntegerConstantExpression(CondExpr, &condEval,
13881 diag::err_typecheck_choose_expr_requires_constant, false);
13882 if (CondICE.isInvalid())
13883 return ExprError();
13884 CondExpr = CondICE.get();
13885 CondIsTrue = condEval.getZExtValue();
13886
13887 // If the condition is > zero, then the AST type is the same as the LHSExpr.
13888 Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
13889
13890 resType = ActiveExpr->getType();
13891 ValueDependent = ActiveExpr->isValueDependent();
13892 VK = ActiveExpr->getValueKind();
13893 OK = ActiveExpr->getObjectKind();
13894 }
13895
13896 return new (Context)
13897 ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, VK, OK, RPLoc,
13898 CondIsTrue, resType->isDependentType(), ValueDependent);
13899}
13900
13901//===----------------------------------------------------------------------===//
13902// Clang Extensions.
13903//===----------------------------------------------------------------------===//
13904
13905/// ActOnBlockStart - This callback is invoked when a block literal is started.
13906void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
13907 BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc);
13908
13909 if (LangOpts.CPlusPlus) {
13910 Decl *ManglingContextDecl;
13911 if (MangleNumberingContext *MCtx =
13912 getCurrentMangleNumberContext(Block->getDeclContext(),
13913 ManglingContextDecl)) {
13914 unsigned ManglingNumber = MCtx->getManglingNumber(Block);
13915 Block->setBlockMangling(ManglingNumber, ManglingContextDecl);
13916 }
13917 }
13918
13919 PushBlockScope(CurScope, Block);
13920 CurContext->addDecl(Block);
13921 if (CurScope)
13922 PushDeclContext(CurScope, Block);
13923 else
13924 CurContext = Block;
13925
13926 getCurBlock()->HasImplicitReturnType = true;
13927
13928 // Enter a new evaluation context to insulate the block from any
13929 // cleanups from the enclosing full-expression.
13930 PushExpressionEvaluationContext(
13931 ExpressionEvaluationContext::PotentiallyEvaluated);
13932}
13933
13934void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
13935 Scope *CurScope) {
13936 assert(ParamInfo.getIdentifier() == nullptr &&
13937 "block-id should have no identifier!");
13938 assert(ParamInfo.getContext() == DeclaratorContext::BlockLiteralContext);
13939 BlockScopeInfo *CurBlock = getCurBlock();
13940
13941 TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope);
13942 QualType T = Sig->getType();
13943
13944 // FIXME: We should allow unexpanded parameter packs here, but that would,
13945 // in turn, make the block expression contain unexpanded parameter packs.
13946 if (DiagnoseUnexpandedParameterPack(CaretLoc, Sig, UPPC_Block)) {
13947 // Drop the parameters.
13948 FunctionProtoType::ExtProtoInfo EPI;
13949 EPI.HasTrailingReturn = false;
13950 EPI.TypeQuals.addConst();
13951 T = Context.getFunctionType(Context.DependentTy, None, EPI);
13952 Sig = Context.getTrivialTypeSourceInfo(T);
13953 }
13954
13955 // GetTypeForDeclarator always produces a function type for a block
13956 // literal signature. Furthermore, it is always a FunctionProtoType
13957 // unless the function was written with a typedef.
13958 assert(T->isFunctionType() &&
13959 "GetTypeForDeclarator made a non-function block signature");
13960
13961 // Look for an explicit signature in that function type.
13962 FunctionProtoTypeLoc ExplicitSignature;
13963
13964 if ((ExplicitSignature = Sig->getTypeLoc()
13965 .getAsAdjusted<FunctionProtoTypeLoc>())) {
13966
13967 // Check whether that explicit signature was synthesized by
13968 // GetTypeForDeclarator. If so, don't save that as part of the
13969 // written signature.
13970 if (ExplicitSignature.getLocalRangeBegin() ==
13971 ExplicitSignature.getLocalRangeEnd()) {
13972 // This would be much cheaper if we stored TypeLocs instead of
13973 // TypeSourceInfos.
13974 TypeLoc Result = ExplicitSignature.getReturnLoc();
13975 unsigned Size = Result.getFullDataSize();
13976 Sig = Context.CreateTypeSourceInfo(Result.getType(), Size);
13977 Sig->getTypeLoc().initializeFullCopy(Result, Size);
13978
13979 ExplicitSignature = FunctionProtoTypeLoc();
13980 }
13981 }
13982
13983 CurBlock->TheDecl->setSignatureAsWritten(Sig);
13984 CurBlock->FunctionType = T;
13985
13986 const FunctionType *Fn = T->getAs<FunctionType>();
13987 QualType RetTy = Fn->getReturnType();
13988 bool isVariadic =
13989 (isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic());
13990
13991 CurBlock->TheDecl->setIsVariadic(isVariadic);
13992
13993 // Context.DependentTy is used as a placeholder for a missing block
13994 // return type. TODO: what should we do with declarators like:
13995 // ^ * { ... }
13996 // If the answer is "apply template argument deduction"....
13997 if (RetTy != Context.DependentTy) {
13998 CurBlock->ReturnType = RetTy;
13999 CurBlock->TheDecl->setBlockMissingReturnType(false);
14000 CurBlock->HasImplicitReturnType = false;
14001 }
14002
14003 // Push block parameters from the declarator if we had them.
14004 SmallVector<ParmVarDecl*, 8> Params;
14005 if (ExplicitSignature) {
14006 for (unsigned I = 0, E = ExplicitSignature.getNumParams(); I != E; ++I) {
14007 ParmVarDecl *Param = ExplicitSignature.getParam(I);
14008 if (Param->getIdentifier() == nullptr &&
14009 !Param->isImplicit() &&
14010 !Param->isInvalidDecl() &&
14011 !getLangOpts().CPlusPlus)
14012 Diag(Param->getLocation(), diag::err_parameter_name_omitted);
14013 Params.push_back(Param);
14014 }
14015
14016 // Fake up parameter variables if we have a typedef, like
14017 // ^ fntype { ... }
14018 } else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) {
14019 for (const auto &I : Fn->param_types()) {
14020 ParmVarDecl *Param = BuildParmVarDeclForTypedef(
14021 CurBlock->TheDecl, ParamInfo.getBeginLoc(), I);
14022 Params.push_back(Param);
14023 }
14024 }
14025
14026 // Set the parameters on the block decl.
14027 if (!Params.empty()) {
14028 CurBlock->TheDecl->setParams(Params);
14029 CheckParmsForFunctionDef(CurBlock->TheDecl->parameters(),
14030 /*CheckParameterNames=*/false);
14031 }
14032
14033 // Finally we can process decl attributes.
14034 ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo);
14035
14036 // Put the parameter variables in scope.
14037 for (auto AI : CurBlock->TheDecl->parameters()) {
14038 AI->setOwningFunction(CurBlock->TheDecl);
14039
14040 // If this has an identifier, add it to the scope stack.
14041 if (AI->getIdentifier()) {
14042 CheckShadow(CurBlock->TheScope, AI);
14043
14044 PushOnScopeChains(AI, CurBlock->TheScope);
14045 }
14046 }
14047}
14048
14049/// ActOnBlockError - If there is an error parsing a block, this callback
14050/// is invoked to pop the information about the block from the action impl.
14051void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
14052 // Leave the expression-evaluation context.
14053 DiscardCleanupsInEvaluationContext();
14054 PopExpressionEvaluationContext();
14055
14056 // Pop off CurBlock, handle nested blocks.
14057 PopDeclContext();
14058 PopFunctionScopeInfo();
14059}
14060
14061/// ActOnBlockStmtExpr - This is called when the body of a block statement
14062/// literal was successfully completed. ^(int x){...}
14063ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
14064 Stmt *Body, Scope *CurScope) {
14065 // If blocks are disabled, emit an error.
14066 if (!LangOpts.Blocks)
14067 Diag(CaretLoc, diag::err_blocks_disable) << LangOpts.OpenCL;
14068
14069 // Leave the expression-evaluation context.
14070 if (hasAnyUnrecoverableErrorsInThisFunction())
14071 DiscardCleanupsInEvaluationContext();
14072 assert(!Cleanup.exprNeedsCleanups() &&
14073 "cleanups within block not correctly bound!");
14074 PopExpressionEvaluationContext();
14075
14076 BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back());
14077 BlockDecl *BD = BSI->TheDecl;
14078
14079 if (BSI->HasImplicitReturnType)
14080 deduceClosureReturnType(*BSI);
14081
14082 QualType RetTy = Context.VoidTy;
14083 if (!BSI->ReturnType.isNull())
14084 RetTy = BSI->ReturnType;
14085
14086 bool NoReturn = BD->hasAttr<NoReturnAttr>();
14087 QualType BlockTy;
14088
14089 // If the user wrote a function type in some form, try to use that.
14090 if (!BSI->FunctionType.isNull()) {
14091 const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>();
14092
14093 FunctionType::ExtInfo Ext = FTy->getExtInfo();
14094 if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true);
14095
14096 // Turn protoless block types into nullary block types.
14097 if (isa<FunctionNoProtoType>(FTy)) {
14098 FunctionProtoType::ExtProtoInfo EPI;
14099 EPI.ExtInfo = Ext;
14100 BlockTy = Context.getFunctionType(RetTy, None, EPI);
14101
14102 // Otherwise, if we don't need to change anything about the function type,
14103 // preserve its sugar structure.
14104 } else if (FTy->getReturnType() == RetTy &&
14105 (!NoReturn || FTy->getNoReturnAttr())) {
14106 BlockTy = BSI->FunctionType;
14107
14108 // Otherwise, make the minimal modifications to the function type.
14109 } else {
14110 const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy);
14111 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
14112 EPI.TypeQuals = Qualifiers();
14113 EPI.ExtInfo = Ext;
14114 BlockTy = Context.getFunctionType(RetTy, FPT->getParamTypes(), EPI);
14115 }
14116
14117 // If we don't have a function type, just build one from nothing.
14118 } else {
14119 FunctionProtoType::ExtProtoInfo EPI;
14120 EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn);
14121 BlockTy = Context.getFunctionType(RetTy, None, EPI);
14122 }
14123
14124 DiagnoseUnusedParameters(BD->parameters());
14125 BlockTy = Context.getBlockPointerType(BlockTy);
14126
14127 // If needed, diagnose invalid gotos and switches in the block.
14128 if (getCurFunction()->NeedsScopeChecking() &&
14129 !PP.isCodeCompletionEnabled())
14130 DiagnoseInvalidJumps(cast<CompoundStmt>(Body));
14131
14132 BD->setBody(cast<CompoundStmt>(Body));
14133
14134 if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
14135 DiagnoseUnguardedAvailabilityViolations(BD);
14136
14137 // Try to apply the named return value optimization. We have to check again
14138 // if we can do this, though, because blocks keep return statements around
14139 // to deduce an implicit return type.
14140 if (getLangOpts().CPlusPlus && RetTy->isRecordType() &&
14141 !BD->isDependentContext())
14142 computeNRVO(Body, BSI);
14143
14144 PopDeclContext();
14145
14146 // Pop the block scope now but keep it alive to the end of this function.
14147 AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
14148 PoppedFunctionScopePtr ScopeRAII = PopFunctionScopeInfo(&WP, BD, BlockTy);
14149
14150 // Set the captured variables on the block.
14151 SmallVector<BlockDecl::Capture, 4> Captures;
14152 for (Capture &Cap : BSI->Captures) {
14153 if (Cap.isInvalid() || Cap.isThisCapture())
14154 continue;
14155
14156 VarDecl *Var = Cap.getVariable();
14157 Expr *CopyExpr = nullptr;
14158 if (getLangOpts().CPlusPlus && Cap.isCopyCapture()) {
14159 if (const RecordType *Record =
14160 Cap.getCaptureType()->getAs<RecordType>()) {
14161 // The capture logic needs the destructor, so make sure we mark it.
14162 // Usually this is unnecessary because most local variables have
14163 // their destructors marked at declaration time, but parameters are
14164 // an exception because it's technically only the call site that
14165 // actually requires the destructor.
14166 if (isa<ParmVarDecl>(Var))
14167 FinalizeVarWithDestructor(Var, Record);
14168
14169 // Enter a separate potentially-evaluated context while building block
14170 // initializers to isolate their cleanups from those of the block
14171 // itself.
14172 // FIXME: Is this appropriate even when the block itself occurs in an
14173 // unevaluated operand?
14174 EnterExpressionEvaluationContext EvalContext(
14175 *this, ExpressionEvaluationContext::PotentiallyEvaluated);
14176
14177 SourceLocation Loc = Cap.getLocation();
14178
14179 ExprResult Result = BuildDeclarationNameExpr(
14180 CXXScopeSpec(), DeclarationNameInfo(Var->getDeclName(), Loc), Var);
14181
14182 // According to the blocks spec, the capture of a variable from
14183 // the stack requires a const copy constructor. This is not true
14184 // of the copy/move done to move a __block variable to the heap.
14185 if (!Result.isInvalid() &&
14186 !Result.get()->getType().isConstQualified()) {
14187 Result = ImpCastExprToType(Result.get(),
14188 Result.get()->getType().withConst(),
14189 CK_NoOp, VK_LValue);
14190 }
14191
14192 if (!Result.isInvalid()) {
14193 Result = PerformCopyInitialization(
14194 InitializedEntity::InitializeBlock(Var->getLocation(),
14195 Cap.getCaptureType(), false),
14196 Loc, Result.get());
14197 }
14198
14199 // Build a full-expression copy expression if initialization
14200 // succeeded and used a non-trivial constructor. Recover from
14201 // errors by pretending that the copy isn't necessary.
14202 if (!Result.isInvalid() &&
14203 !cast<CXXConstructExpr>(Result.get())->getConstructor()
14204 ->isTrivial()) {
14205 Result = MaybeCreateExprWithCleanups(Result);
14206 CopyExpr = Result.get();
14207 }
14208 }
14209 }
14210
14211 BlockDecl::Capture NewCap(Var, Cap.isBlockCapture(), Cap.isNested(),
14212 CopyExpr);
14213 Captures.push_back(NewCap);
14214 }
14215 BD->setCaptures(Context, Captures, BSI->CXXThisCaptureIndex != 0);
14216
14217 BlockExpr *Result = new (Context) BlockExpr(BD, BlockTy);
14218
14219 // If the block isn't obviously global, i.e. it captures anything at
14220 // all, then we need to do a few things in the surrounding context:
14221 if (Result->getBlockDecl()->hasCaptures()) {
14222 // First, this expression has a new cleanup object.
14223 ExprCleanupObjects.push_back(Result->getBlockDecl());
14224 Cleanup.setExprNeedsCleanups(true);
14225
14226 // It also gets a branch-protected scope if any of the captured
14227 // variables needs destruction.
14228 for (const auto &CI : Result->getBlockDecl()->captures()) {
14229 const VarDecl *var = CI.getVariable();
14230 if (var->getType().isDestructedType() != QualType::DK_none) {
14231 setFunctionHasBranchProtectedScope();
14232 break;
14233 }
14234 }
14235 }
14236
14237 if (getCurFunction())
14238 getCurFunction()->addBlock(BD);
14239
14240 return Result;
14241}
14242
14243ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
14244 SourceLocation RPLoc) {
14245 TypeSourceInfo *TInfo;
14246 GetTypeFromParser(Ty, &TInfo);
14247 return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc);
14248}
14249
14250ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
14251 Expr *E, TypeSourceInfo *TInfo,
14252 SourceLocation RPLoc) {
14253 Expr *OrigExpr = E;
14254 bool IsMS = false;
14255
14256 // CUDA device code does not support varargs.
14257 if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
14258 if (const FunctionDecl *F = dyn_cast<FunctionDecl>(CurContext)) {
14259 CUDAFunctionTarget T = IdentifyCUDATarget(F);
14260 if (T == CFT_Global || T == CFT_Device || T == CFT_HostDevice)
14261 return ExprError(Diag(E->getBeginLoc(), diag::err_va_arg_in_device));
14262 }
14263 }
14264
14265 // NVPTX does not support va_arg expression.
14266 if (getLangOpts().OpenMP && getLangOpts().OpenMPIsDevice &&
14267 Context.getTargetInfo().getTriple().isNVPTX())
14268 targetDiag(E->getBeginLoc(), diag::err_va_arg_in_device);
14269
14270 // It might be a __builtin_ms_va_list. (But don't ever mark a va_arg()
14271 // as Microsoft ABI on an actual Microsoft platform, where
14272 // __builtin_ms_va_list and __builtin_va_list are the same.)
14273 if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList() &&
14274 Context.getTargetInfo().getBuiltinVaListKind() != TargetInfo::CharPtrBuiltinVaList) {
14275 QualType MSVaListType = Context.getBuiltinMSVaListType();
14276 if (Context.hasSameType(MSVaListType, E->getType())) {
14277 if (CheckForModifiableLvalue(E, BuiltinLoc, *this))
14278 return ExprError();
14279 IsMS = true;
14280 }
14281 }
14282
14283 // Get the va_list type
14284 QualType VaListType = Context.getBuiltinVaListType();
14285 if (!IsMS) {
14286 if (VaListType->isArrayType()) {
14287 // Deal with implicit array decay; for example, on x86-64,
14288 // va_list is an array, but it's supposed to decay to
14289 // a pointer for va_arg.
14290 VaListType = Context.getArrayDecayedType(VaListType);
14291 // Make sure the input expression also decays appropriately.
14292 ExprResult Result = UsualUnaryConversions(E);
14293 if (Result.isInvalid())
14294 return ExprError();
14295 E = Result.get();
14296 } else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) {
14297 // If va_list is a record type and we are compiling in C++ mode,
14298 // check the argument using reference binding.
14299 InitializedEntity Entity = InitializedEntity::InitializeParameter(
14300 Context, Context.getLValueReferenceType(VaListType), false);
14301 ExprResult Init = PerformCopyInitialization(Entity, SourceLocation(), E);
14302 if (Init.isInvalid())
14303 return ExprError();
14304 E = Init.getAs<Expr>();
14305 } else {
14306 // Otherwise, the va_list argument must be an l-value because
14307 // it is modified by va_arg.
14308 if (!E->isTypeDependent() &&
14309 CheckForModifiableLvalue(E, BuiltinLoc, *this))
14310 return ExprError();
14311 }
14312 }
14313
14314 if (!IsMS && !E->isTypeDependent() &&
14315 !Context.hasSameType(VaListType, E->getType()))
14316 return ExprError(
14317 Diag(E->getBeginLoc(),
14318 diag::err_first_argument_to_va_arg_not_of_type_va_list)
14319 << OrigExpr->getType() << E->getSourceRange());
14320
14321 if (!TInfo->getType()->isDependentType()) {
14322 if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(),
14323 diag::err_second_parameter_to_va_arg_incomplete,
14324 TInfo->getTypeLoc()))
14325 return ExprError();
14326
14327 if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(),
14328 TInfo->getType(),
14329 diag::err_second_parameter_to_va_arg_abstract,
14330 TInfo->getTypeLoc()))
14331 return ExprError();
14332
14333 if (!TInfo->getType().isPODType(Context)) {
14334 Diag(TInfo->getTypeLoc().getBeginLoc(),
14335 TInfo->getType()->isObjCLifetimeType()
14336 ? diag::warn_second_parameter_to_va_arg_ownership_qualified
14337 : diag::warn_second_parameter_to_va_arg_not_pod)
14338 << TInfo->getType()
14339 << TInfo->getTypeLoc().getSourceRange();
14340 }
14341
14342 // Check for va_arg where arguments of the given type will be promoted
14343 // (i.e. this va_arg is guaranteed to have undefined behavior).
14344 QualType PromoteType;
14345 if (TInfo->getType()->isPromotableIntegerType()) {
14346 PromoteType = Context.getPromotedIntegerType(TInfo->getType());
14347 if (Context.typesAreCompatible(PromoteType, TInfo->getType()))
14348 PromoteType = QualType();
14349 }
14350 if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float))
14351 PromoteType = Context.DoubleTy;
14352 if (!PromoteType.isNull())
14353 DiagRuntimeBehavior(TInfo->getTypeLoc().getBeginLoc(), E,
14354 PDiag(diag::warn_second_parameter_to_va_arg_never_compatible)
14355 << TInfo->getType()
14356 << PromoteType
14357 << TInfo->getTypeLoc().getSourceRange());
14358 }
14359
14360 QualType T = TInfo->getType().getNonLValueExprType(Context);
14361 return new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T, IsMS);
14362}
14363
14364ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
14365 // The type of __null will be int or long, depending on the size of
14366 // pointers on the target.
14367 QualType Ty;
14368 const auto& TI = Context.getTargetInfo();
14369 unsigned pw = TI.getPointerWidth(0);
14370 if (TI.areAllPointersCapabilities() && pw == TI.getIntCapWidth())
14371 Ty = Context.IntCapTy;
14372 else if (pw == TI.getIntWidth())
14373 Ty = Context.IntTy;
14374 else if (pw == TI.getLongWidth())
14375 Ty = Context.LongTy;
14376 else if (pw == TI.getLongLongWidth())
14377 Ty = Context.LongLongTy;
14378 else {
14379 llvm_unreachable("I don't know size of pointer!");
14380 }
14381
14382 return new (Context) GNUNullExpr(Ty, TokenLoc);
14383}
14384
14385ExprResult Sema::ActOnSourceLocExpr(SourceLocExpr::IdentKind Kind,
14386 SourceLocation BuiltinLoc,
14387 SourceLocation RPLoc) {
14388 return BuildSourceLocExpr(Kind, BuiltinLoc, RPLoc, CurContext);
14389}
14390
14391ExprResult Sema::BuildSourceLocExpr(SourceLocExpr::IdentKind Kind,
14392 SourceLocation BuiltinLoc,
14393 SourceLocation RPLoc,
14394 DeclContext *ParentContext) {
14395 return new (Context)
14396 SourceLocExpr(Context, Kind, BuiltinLoc, RPLoc, ParentContext);
14397}
14398
14399bool Sema::ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&Exp,
14400 bool Diagnose) {
14401 if (!getLangOpts().ObjC)
14402 return false;
14403
14404 const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>();
14405 if (!PT)
14406 return false;
14407
14408 if (!PT->isObjCIdType()) {
14409 // Check if the destination is the 'NSString' interface.
14410 const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
14411 if (!ID || !ID->getIdentifier()->isStr("NSString"))
14412 return false;
14413 }
14414
14415 // Ignore any parens, implicit casts (should only be
14416 // array-to-pointer decays), and not-so-opaque values. The last is
14417 // important for making this trigger for property assignments.
14418 Expr *SrcExpr = Exp->IgnoreParenImpCasts();
14419 if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr))
14420 if (OV->getSourceExpr())
14421 SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts();
14422
14423 StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr);
14424 if (!SL || !SL->isAscii())
14425 return false;
14426 if (Diagnose) {
14427 Diag(SL->getBeginLoc(), diag::err_missing_atsign_prefix)
14428 << FixItHint::CreateInsertion(SL->getBeginLoc(), "@");
14429 Exp = BuildObjCStringLiteral(SL->getBeginLoc(), SL).get();
14430 }
14431 return true;
14432}
14433
14434static bool maybeDiagnoseAssignmentToFunction(Sema &S, QualType DstType,
14435 const Expr *SrcExpr) {
14436 if (!DstType->isFunctionPointerType() ||
14437 !SrcExpr->getType()->isFunctionType())
14438 return false;
14439
14440 auto *DRE = dyn_cast<DeclRefExpr>(SrcExpr->IgnoreParenImpCasts());
14441 if (!DRE)
14442 return false;
14443
14444 auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
14445 if (!FD)
14446 return false;
14447
14448 return !S.checkAddressOfFunctionIsAvailable(FD,
14449 /*Complain=*/true,
14450 SrcExpr->getBeginLoc());
14451}
14452
14453static void diagnoseBadVariadicFunctionPointerAssignment(Sema &S,
14454 SourceLocation Loc,
14455 QualType SrcType,
14456 QualType DstType,
14457 Expr* SrcExpr) {
14458 const FunctionType *DstFnTy =
14459 DstType->getPointeeType()->getAs<FunctionType>();
14460
14461 const FunctionType *SrcFnTy = nullptr;
14462 if (SrcType->isFunctionPointerType())
14463 SrcFnTy = SrcType->getPointeeType()->getAs<FunctionType>();
14464 else
14465 SrcFnTy = SrcType->getAs<FunctionType>();
14466 // TODO: also diagnose any variadic to non-variadic
14467 // TODO: don't warn about zero-arg function
14468 if (!SrcFnTy)
14469 return; // Should give an invalid pointer to function warning anyway
14470
14471 FunctionDecl* FuncDecl = nullptr;
14472 // Avoid warnings for K&R functions where we actually know the prototype:
14473 if (auto *UO = dyn_cast<UnaryOperator>(SrcExpr->IgnoreImplicit())) {
14474 // look through &foo to find the actual function
14475 if (UO->getOpcode() == UO_AddrOf)
14476 SrcExpr = UO->getSubExpr();
14477 }
14478 if (auto *DRE = dyn_cast<DeclRefExpr>(SrcExpr->IgnoreImplicit())) {
14479 FuncDecl = dyn_cast<FunctionDecl>(DRE->getDecl());
14480 }
14481
14482 enum class CCType { NoProto, Variadic, FixedArg, Invalid };
14483 CCType SrcCCType = CCType::Invalid;
14484 if (SrcFnTy->isFunctionNoProtoType()) {
14485 // Type is noproto but we might have a decl with the real prototype:
14486 if (FuncDecl)
14487 SrcFnTy = FuncDecl->getType()->getAs<FunctionType>();
14488 // Now check again to see if it is still a noproto type
14489 if (SrcFnTy->isFunctionNoProtoType())
14490 SrcCCType = CCType::NoProto;
14491 }
14492 if (auto *SrcProto = SrcFnTy->getAs<FunctionProtoType>()) {
14493 // assigning a function without parameters is fine since there will never be
14494 // any confusion between on-stack and in-register arguments
14495 if (SrcProto->getNumParams() == 0)
14496 return;
14497 SrcCCType = SrcProto->isVariadic() ? CCType::Variadic : CCType::FixedArg;
14498 }
14499 CCType DstCCType = CCType::Invalid;
14500 if (DstFnTy->isFunctionNoProtoType())
14501 DstCCType = CCType::NoProto;
14502 else if (auto *DstProto = DstFnTy->getAs<FunctionProtoType>()) {
14503 DstCCType = DstProto->isVariadic() ? CCType::Variadic : CCType::FixedArg;
14504 }
14505 assert(SrcCCType != CCType::Invalid);
14506 assert(DstCCType != CCType::Invalid);
14507
14508 if (SrcCCType != DstCCType) {
14509 // converting variadic to non-variadic is an error by default, the other is
14510 // a pedantic warning that is often a false positive
14511 unsigned DiagID = diag::warn_mips_cheri_fnptr_proto_noproto_conversion;
14512 unsigned ExplainID = diag::note_mips_cheri_func_noproto_explanation;
14513 if (SrcCCType == CCType::Variadic || DstCCType == CCType::Variadic) {
14514 DiagID = diag::warn_mips_cheri_fnptr_variadic_nonvariadic_conversion;
14515 ExplainID = diag::note_mips_cheri_func_variadic_explanation;
14516 }
14517 S.Diag(Loc, DiagID) << (int)SrcCCType << SrcType << (int)DstCCType
14518 << DstType;
14519 S.Diag(Loc, ExplainID);
14520 if (FuncDecl)
14521 S.Diag(FuncDecl->getBeginLoc(), diag::note_callee_decl) << FuncDecl;
14522 }
14523}
14524
14525bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
14526 SourceLocation Loc,
14527 QualType DstType, QualType SrcType,
14528 Expr *SrcExpr, AssignmentAction Action,
14529 bool *Complained) {
14530 if (Complained)
14531 *Complained = false;
14532
14533 // Decode the result (notice that AST's are still created for extensions).
14534 bool CheckInferredResultType = false;
14535 bool isInvalid = false;
14536 unsigned DiagKind = 0;
14537 FixItHint Hint;
14538 ConversionFixItGenerator ConvHints;
14539 bool MayHaveConvFixit = false;
14540 bool MayHaveFunctionDiff = false;
14541 const ObjCInterfaceDecl *IFace = nullptr;
14542 const ObjCProtocolDecl *PDecl = nullptr;
14543
14544 // Warn when assigning non-variadic functions to variadic function pointers
14545 // and the other way around
14546 // TODO: this should probably be upstreamed as it is not CHERI specific
14547 // TODO: only for Context.getTargetInfo().areAllPointersCapabilities()?
14548 // Note: we need to do this even if ConvTy == compatible since pointers without
14549 // prototypes can be assigned to from any function pointer type
14550 if (DstType->isFunctionPointerType())
14551 diagnoseBadVariadicFunctionPointerAssignment(*this, Loc, SrcType, DstType, SrcExpr);
14552
14553 switch (ConvTy) {
14554 case Compatible:
14555 DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr);
14556 return false;
14557
14558 case PointerToInt:
14559 DiagKind = diag::ext_typecheck_convert_pointer_int;
14560 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
14561 MayHaveConvFixit = true;
14562 break;
14563 case IntToPointer:
14564 DiagKind = diag::ext_typecheck_convert_int_pointer;
14565 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
14566 MayHaveConvFixit = true;
14567 break;
14568 case IncompatiblePointer:
14569 if (Action == AA_Passing_CFAudited)
14570 DiagKind = diag::err_arc_typecheck_convert_incompatible_pointer;
14571 else if (SrcType->isFunctionPointerType() &&
14572 DstType->isFunctionPointerType())
14573 DiagKind = diag::ext_typecheck_convert_incompatible_function_pointer;
14574 else
14575 DiagKind = diag::ext_typecheck_convert_incompatible_pointer;
14576
14577 CheckInferredResultType = DstType->isObjCObjectPointerType() &&
14578 SrcType->isObjCObjectPointerType();
14579 if (Hint.isNull() && !CheckInferredResultType) {
14580 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
14581 }
14582 else if (CheckInferredResultType) {
14583 SrcType = SrcType.getUnqualifiedType();
14584 DstType = DstType.getUnqualifiedType();
14585 }
14586 MayHaveConvFixit = true;
14587 break;
14588 case IncompatiblePointerSign:
14589 DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign;
14590 break;
14591 case FunctionVoidPointer:
14592 DiagKind = diag::ext_typecheck_convert_pointer_void_func;
14593 break;
14594 case IncompatiblePointerDiscardsQualifiers: {
14595 // Perform array-to-pointer decay if necessary.
14596 if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType);
14597
14598 Qualifiers lhq = SrcType->getPointeeType().getQualifiers();
14599 Qualifiers rhq = DstType->getPointeeType().getQualifiers();
14600 if (lhq.getAddressSpace() != rhq.getAddressSpace()) {
14601 DiagKind = diag::err_typecheck_incompatible_address_space;
14602 break;
14603
14604 } else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) {
14605 DiagKind = diag::err_typecheck_incompatible_ownership;
14606 break;
14607 }
14608
14609 llvm_unreachable("unknown error case for discarding qualifiers!");
14610 // fallthrough
14611 }
14612 case CompatiblePointerDiscardsQualifiers:
14613 // If the qualifiers lost were because we were applying the
14614 // (deprecated) C++ conversion from a string literal to a char*
14615 // (or wchar_t*), then there was no error (C++ 4.2p2). FIXME:
14616 // Ideally, this check would be performed in
14617 // checkPointerTypesForAssignment. However, that would require a
14618 // bit of refactoring (so that the second argument is an
14619 // expression, rather than a type), which should be done as part
14620 // of a larger effort to fix checkPointerTypesForAssignment for
14621 // C++ semantics.
14622 if (getLangOpts().CPlusPlus &&
14623 IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType))
14624 return false;
14625 DiagKind = diag::ext_typecheck_convert_discards_qualifiers;
14626 break;
14627 case IncompatibleNestedPointerQualifiers:
14628 DiagKind = diag::ext_nested_pointer_qualifier_mismatch;
14629 break;
14630 case IncompatibleNestedPointerAddressSpaceMismatch:
14631 DiagKind = diag::err_typecheck_incompatible_nested_address_space;
14632 break;
14633 case IntToBlockPointer:
14634 DiagKind = diag::err_int_to_block_pointer;
14635 break;
14636 case IncompatibleBlockPointer:
14637 DiagKind = diag::err_typecheck_convert_incompatible_block_pointer;
14638 break;
14639 case IncompatibleObjCQualifiedId: {
14640 if (SrcType->isObjCQualifiedIdType()) {
14641 const ObjCObjectPointerType *srcOPT =
14642 SrcType->getAs<ObjCObjectPointerType>();
14643 for (auto *srcProto : srcOPT->quals()) {
14644 PDecl = srcProto;
14645 break;
14646 }
14647 if (const ObjCInterfaceType *IFaceT =
14648 DstType->getAs<ObjCObjectPointerType>()->getInterfaceType())
14649 IFace = IFaceT->getDecl();
14650 }
14651 else if (DstType->isObjCQualifiedIdType()) {
14652 const ObjCObjectPointerType *dstOPT =
14653 DstType->getAs<ObjCObjectPointerType>();
14654 for (auto *dstProto : dstOPT->quals()) {
14655 PDecl = dstProto;
14656 break;
14657 }
14658 if (const ObjCInterfaceType *IFaceT =
14659 SrcType->getAs<ObjCObjectPointerType>()->getInterfaceType())
14660 IFace = IFaceT->getDecl();
14661 }
14662 DiagKind = diag::warn_incompatible_qualified_id;
14663 break;
14664 }
14665 case IncompatibleVectors:
14666 DiagKind = diag::warn_incompatible_vectors;
14667 break;
14668 case IncompatibleObjCWeakRef:
14669 DiagKind = diag::err_arc_weak_unavailable_assign;
14670 break;
14671 case CHERICapabilityToPointer:
14672 case PointerToCHERICapability: {
14673 bool PtrToCap = ConvTy == PointerToCHERICapability;
14674
14675 if (PtrToCap) {
14676 // first perform array|function to pointer decay
14677 ExprResult Decayed = DefaultFunctionArrayLvalueConversion(SrcExpr);
14678 if (Decayed.isInvalid()) {
14679 isInvalid = true;
14680 return true;
14681 break;
14682 }
14683 SrcExpr = Decayed.get();
14684 SrcType = SrcExpr->getType();
14685 if (ImpCastPointerToCHERICapability(SrcType, DstType, SrcExpr, false))
14686 return false;
14687 }
14688
14689 // If we reach here, output an error
14690 DiagKind = PtrToCap ? diag::err_typecheck_convert_ptr_to_cap
14691 : diag::err_typecheck_convert_cap_to_ptr;
14692 MayHaveConvFixit = true;
14693 isInvalid = true;
14694 Hint = FixItHint::CreateInsertion(SrcExpr->getBeginLoc(), "(__cheri_" +
14695 std::string(PtrToCap ? "to" : "from") +
14696 "cap " + DstType.getAsString() + ")");
14697 Diag(Loc, DiagKind) << SrcType << DstType << false << Hint;
14698 return true;
14699 break;
14700 }
14701 case Incompatible:
14702 if (maybeDiagnoseAssignmentToFunction(*this, DstType, SrcExpr)) {
14703 if (Complained)
14704 *Complained = true;
14705 return true;
14706 }
14707
14708 // CHERI: in the case of implicit conversion of address-of expressions to capabilities,
14709 // output error message here if the types are not compatible, so that we
14710 // get the same error message for both C and C++.
14711 if (SrcType->isPointerType()
14712 && !SrcType->isCHERICapabilityType(Context, false)
14713 && DstType->isCHERICapabilityType(Context, false)) {
14714 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(SrcExpr)) {
14715 if (UnOp->getOpcode() == UO_AddrOf) {
14716 Diag(SrcExpr->getExprLoc(), diag::err_typecheck_convert_ptr_to_cap_unrelated_type)
14717 << SrcType << DstType << false;
14718 return true;
14719 }
14720 }
14721 }
14722
14723 DiagKind = diag::err_typecheck_convert_incompatible;
14724 ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
14725 MayHaveConvFixit = true;
14726 isInvalid = true;
14727 MayHaveFunctionDiff = true;
14728 break;
14729 }
14730
14731 QualType FirstType, SecondType;
14732 switch (Action) {
14733 case AA_Assigning:
14734 case AA_Initializing:
14735 // The destination type comes first.
14736 FirstType = DstType;
14737 SecondType = SrcType;
14738 break;
14739
14740 case AA_Returning:
14741 case AA_Passing:
14742 case AA_Passing_CFAudited:
14743 case AA_Converting:
14744 case AA_Sending:
14745 case AA_Casting:
14746 // The source type comes first.
14747 FirstType = SrcType;
14748 SecondType = DstType;
14749 break;
14750 }
14751
14752 PartialDiagnostic FDiag = PDiag(DiagKind);
14753 if (Action == AA_Passing_CFAudited)
14754 FDiag << FirstType << SecondType << AA_Passing << SrcExpr->getSourceRange();
14755 else
14756 FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange();
14757
14758 // If we can fix the conversion, suggest the FixIts.
14759 assert(ConvHints.isNull() || Hint.isNull());
14760 if (!ConvHints.isNull()) {
14761 for (FixItHint &H : ConvHints.Hints)
14762 FDiag << H;
14763 } else {
14764 FDiag << Hint;
14765 }
14766 if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); }
14767
14768 if (MayHaveFunctionDiff)
14769 HandleFunctionTypeMismatch(FDiag, SecondType, FirstType);
14770
14771 Diag(Loc, FDiag);
14772 if (DiagKind == diag::warn_incompatible_qualified_id &&
14773 PDecl && IFace && !IFace->hasDefinition())
14774 Diag(IFace->getLocation(), diag::note_incomplete_class_and_qualified_id)
14775 << IFace << PDecl;
14776
14777 if (SecondType == Context.OverloadTy)
14778 NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression,
14779 FirstType, /*TakingAddress=*/true);
14780
14781 if (CheckInferredResultType)
14782 EmitRelatedResultTypeNote(SrcExpr);
14783
14784 if (Action == AA_Returning && ConvTy == IncompatiblePointer)
14785 EmitRelatedResultTypeNoteForReturn(DstType);
14786
14787 if (Complained)
14788 *Complained = true;
14789 return isInvalid;
14790}
14791
14792ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
14793 llvm::APSInt *Result) {
14794 class SimpleICEDiagnoser : public VerifyICEDiagnoser {
14795 public:
14796 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
14797 S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus << SR;
14798 }
14799 } Diagnoser;
14800
14801 return VerifyIntegerConstantExpression(E, Result, Diagnoser);
14802}
14803
14804ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
14805 llvm::APSInt *Result,
14806 unsigned DiagID,
14807 bool AllowFold) {
14808 class IDDiagnoser : public VerifyICEDiagnoser {
14809 unsigned DiagID;
14810
14811 public:
14812 IDDiagnoser(unsigned DiagID)
14813 : VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
14814
14815 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
14816 S.Diag(Loc, DiagID) << SR;
14817 }
14818 } Diagnoser(DiagID);
14819
14820 return VerifyIntegerConstantExpression(E, Result, Diagnoser, AllowFold);
14821}
14822
14823void Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc,
14824 SourceRange SR) {
14825 S.Diag(Loc, diag::ext_expr_not_ice) << SR << S.LangOpts.CPlusPlus;
14826}
14827
14828ExprResult
14829Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
14830 VerifyICEDiagnoser &Diagnoser,
14831 bool AllowFold) {
14832 SourceLocation DiagLoc = E->getBeginLoc();
14833
14834 if (getLangOpts().CPlusPlus11) {
14835 // C++11 [expr.const]p5:
14836 // If an expression of literal class type is used in a context where an
14837 // integral constant expression is required, then that class type shall
14838 // have a single non-explicit conversion function to an integral or
14839 // unscoped enumeration type
14840 ExprResult Converted;
14841 class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
14842 public:
14843 CXX11ConvertDiagnoser(bool Silent)
14844 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false,
14845 Silent, true) {}
14846
14847 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
14848 QualType T) override {
14849 return S.Diag(Loc, diag::err_ice_not_integral) << T;
14850 }
14851
14852 SemaDiagnosticBuilder diagnoseIncomplete(
14853 Sema &S, SourceLocation Loc, QualType T) override {
14854 return S.Diag(Loc, diag::err_ice_incomplete_type) << T;
14855 }
14856
14857 SemaDiagnosticBuilder diagnoseExplicitConv(
14858 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
14859 return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy;
14860 }
14861
14862 SemaDiagnosticBuilder noteExplicitConv(
14863 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
14864 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
14865 << ConvTy->isEnumeralType() << ConvTy;
14866 }
14867
14868 SemaDiagnosticBuilder diagnoseAmbiguous(
14869 Sema &S, SourceLocation Loc, QualType T) override {
14870 return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T;
14871 }
14872
14873 SemaDiagnosticBuilder noteAmbiguous(
14874 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
14875 return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
14876 << ConvTy->isEnumeralType() << ConvTy;
14877 }
14878
14879 SemaDiagnosticBuilder diagnoseConversion(
14880 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
14881 llvm_unreachable("conversion functions are permitted");
14882 }
14883 } ConvertDiagnoser(Diagnoser.Suppress);
14884
14885 Converted = PerformContextualImplicitConversion(DiagLoc, E,
14886 ConvertDiagnoser);
14887 if (Converted.isInvalid())
14888 return Converted;
14889 E = Converted.get();
14890 if (!E->getType()->isIntegralOrUnscopedEnumerationType())
14891 return ExprError();
14892 } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
14893 // An ICE must be of integral or unscoped enumeration type.
14894 if (!Diagnoser.Suppress)
14895 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
14896 return ExprError();
14897 }
14898
14899 if (!isa<ConstantExpr>(E))
14900 E = ConstantExpr::Create(Context, E);
14901
14902 // Circumvent ICE checking in C++11 to avoid evaluating the expression twice
14903 // in the non-ICE case.
14904 if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Context)) {
14905 if (Result)
14906 *Result = E->EvaluateKnownConstIntCheckOverflow(Context);
14907 return E;
14908 }
14909
14910 Expr::EvalResult EvalResult;
14911 SmallVector<PartialDiagnosticAt, 8> Notes;
14912 EvalResult.Diag = &Notes;
14913
14914 // Try to evaluate the expression, and produce diagnostics explaining why it's
14915 // not a constant expression as a side-effect.
14916 bool Folded = E->EvaluateAsRValue(EvalResult, Context) &&
14917 EvalResult.Val.isInt() && !EvalResult.HasSideEffects;
14918
14919 // In C++11, we can rely on diagnostics being produced for any expression
14920 // which is not a constant expression. If no diagnostics were produced, then
14921 // this is a constant expression.
14922 if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) {
14923 if (Result)
14924 *Result = EvalResult.Val.getInt();
14925 return E;
14926 }
14927
14928 // If our only note is the usual "invalid subexpression" note, just point
14929 // the caret at its location rather than producing an essentially
14930 // redundant note.
14931 if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
14932 diag::note_invalid_subexpr_in_const_expr) {
14933 DiagLoc = Notes[0].first;
14934 Notes.clear();
14935 }
14936
14937 if (!Folded || !AllowFold) {
14938 if (!Diagnoser.Suppress) {
14939 Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
14940 for (const PartialDiagnosticAt &Note : Notes)
14941 Diag(Note.first, Note.second);
14942 }
14943
14944 return ExprError();
14945 }
14946
14947 Diagnoser.diagnoseFold(*this, DiagLoc, E->getSourceRange());
14948 for (const PartialDiagnosticAt &Note : Notes)
14949 Diag(Note.first, Note.second);
14950
14951 if (Result)
14952 *Result = EvalResult.Val.getInt();
14953 return E;
14954}
14955
14956namespace {
14957 // Handle the case where we conclude a expression which we speculatively
14958 // considered to be unevaluated is actually evaluated.
14959 class TransformToPE : public TreeTransform<TransformToPE> {
14960 typedef TreeTransform<TransformToPE> BaseTransform;
14961
14962 public:
14963 TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { }
14964
14965 // Make sure we redo semantic analysis
14966 bool AlwaysRebuild() { return true; }
14967 bool ReplacingOriginal() { return true; }
14968
14969 // We need to special-case DeclRefExprs referring to FieldDecls which
14970 // are not part of a member pointer formation; normal TreeTransforming
14971 // doesn't catch this case because of the way we represent them in the AST.
14972 // FIXME: This is a bit ugly; is it really the best way to handle this
14973 // case?
14974 //
14975 // Error on DeclRefExprs referring to FieldDecls.
14976 ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
14977 if (isa<FieldDecl>(E->getDecl()) &&
14978 !SemaRef.isUnevaluatedContext())
14979 return SemaRef.Diag(E->getLocation(),
14980 diag::err_invalid_non_static_member_use)
14981 << E->getDecl() << E->getSourceRange();
14982
14983 return BaseTransform::TransformDeclRefExpr(E);
14984 }
14985
14986 // Exception: filter out member pointer formation
14987 ExprResult TransformUnaryOperator(UnaryOperator *E) {
14988 if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType())
14989 return E;
14990
14991 return BaseTransform::TransformUnaryOperator(E);
14992 }
14993
14994 // The body of a lambda-expression is in a separate expression evaluation
14995 // context so never needs to be transformed.
14996 // FIXME: Ideally we wouldn't transform the closure type either, and would
14997 // just recreate the capture expressions and lambda expression.
14998 StmtResult TransformLambdaBody(LambdaExpr *E, Stmt *Body) {
14999 return SkipLambdaBody(E, Body);
15000 }
15001 };
15002}
15003
15004ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) {
15005 assert(isUnevaluatedContext() &&
15006 "Should only transform unevaluated expressions");
15007 ExprEvalContexts.back().Context =
15008 ExprEvalContexts[ExprEvalContexts.size()-2].Context;
15009 if (isUnevaluatedContext())
15010 return E;
15011 return TransformToPE(*this).TransformExpr(E);
15012}
15013
15014void
15015Sema::PushExpressionEvaluationContext(
15016 ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl,
15017 ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
15018 ExprEvalContexts.emplace_back(NewContext, ExprCleanupObjects.size(), Cleanup,
15019 LambdaContextDecl, ExprContext);
15020 Cleanup.reset();
15021 if (!MaybeODRUseExprs.empty())
15022 std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs);
15023}
15024
15025void
15026Sema::PushExpressionEvaluationContext(
15027 ExpressionEvaluationContext NewContext, ReuseLambdaContextDecl_t,
15028 ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
15029 Decl *ClosureContextDecl = ExprEvalContexts.back().ManglingContextDecl;
15030 PushExpressionEvaluationContext(NewContext, ClosureContextDecl, ExprContext);
15031}
15032
15033namespace {
15034
15035const DeclRefExpr *CheckPossibleDeref(Sema &S, const Expr *PossibleDeref) {
15036 PossibleDeref = PossibleDeref->IgnoreParenImpCasts();
15037 if (const auto *E = dyn_cast<UnaryOperator>(PossibleDeref)) {
15038 if (E->getOpcode() == UO_Deref)
15039 return CheckPossibleDeref(S, E->getSubExpr());
15040 } else if (const auto *E = dyn_cast<ArraySubscriptExpr>(PossibleDeref)) {
15041 return CheckPossibleDeref(S, E->getBase());
15042 } else if (const auto *E = dyn_cast<MemberExpr>(PossibleDeref)) {
15043 return CheckPossibleDeref(S, E->getBase());
15044 } else if (const auto E = dyn_cast<DeclRefExpr>(PossibleDeref)) {
15045 QualType Inner;
15046 QualType Ty = E->getType();
15047 if (const auto *Ptr = Ty->getAs<PointerType>())
15048 Inner = Ptr->getPointeeType();
15049 else if (const auto *Arr = S.Context.getAsArrayType(Ty))
15050 Inner = Arr->getElementType();
15051 else
15052 return nullptr;
15053
15054 if (Inner->hasAttr(attr::NoDeref))
15055 return E;
15056 }
15057 return nullptr;
15058}
15059
15060} // namespace
15061
15062void Sema::WarnOnPendingNoDerefs(ExpressionEvaluationContextRecord &Rec) {
15063 for (const Expr *E : Rec.PossibleDerefs) {
15064 const DeclRefExpr *DeclRef = CheckPossibleDeref(*this, E);
15065 if (DeclRef) {
15066 const ValueDecl *Decl = DeclRef->getDecl();
15067 Diag(E->getExprLoc(), diag::warn_dereference_of_noderef_type)
15068 << Decl->getName() << E->getSourceRange();
15069 Diag(Decl->getLocation(), diag::note_previous_decl) << Decl->getName();
15070 } else {
15071 Diag(E->getExprLoc(), diag::warn_dereference_of_noderef_type_no_decl)
15072 << E->getSourceRange();
15073 }
15074 }
15075 Rec.PossibleDerefs.clear();
15076}
15077
15078void Sema::PopExpressionEvaluationContext() {
15079 ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back();
15080 unsigned NumTypos = Rec.NumTypos;
15081
15082 if (!Rec.Lambdas.empty()) {
15083 using ExpressionKind = ExpressionEvaluationContextRecord::ExpressionKind;
15084 if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument || Rec.isUnevaluated() ||
15085 (Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17)) {
15086 unsigned D;
15087 if (Rec.isUnevaluated()) {
15088 // C++11 [expr.prim.lambda]p2:
15089 // A lambda-expression shall not appear in an unevaluated operand
15090 // (Clause 5).
15091 D = diag::err_lambda_unevaluated_operand;
15092 } else if (Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17) {
15093 // C++1y [expr.const]p2:
15094 // A conditional-expression e is a core constant expression unless the
15095 // evaluation of e, following the rules of the abstract machine, would
15096 // evaluate [...] a lambda-expression.
15097 D = diag::err_lambda_in_constant_expression;
15098 } else if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument) {
15099 // C++17 [expr.prim.lamda]p2:
15100 // A lambda-expression shall not appear [...] in a template-argument.
15101 D = diag::err_lambda_in_invalid_context;
15102 } else
15103 llvm_unreachable("Couldn't infer lambda error message.");
15104
15105 for (const auto *L : Rec.Lambdas)
15106 Diag(L->getBeginLoc(), D);
15107 }
15108 }
15109
15110 WarnOnPendingNoDerefs(Rec);
15111
15112 // When are coming out of an unevaluated context, clear out any
15113 // temporaries that we may have created as part of the evaluation of
15114 // the expression in that context: they aren't relevant because they
15115 // will never be constructed.
15116 if (Rec.isUnevaluated() || Rec.isConstantEvaluated()) {
15117 ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects,
15118 ExprCleanupObjects.end());
15119 Cleanup = Rec.ParentCleanup;
15120 CleanupVarDeclMarking();
15121 std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs);
15122 // Otherwise, merge the contexts together.
15123 } else {
15124 Cleanup.mergeFrom(Rec.ParentCleanup);
15125 MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(),
15126 Rec.SavedMaybeODRUseExprs.end());
15127 }
15128
15129 // Pop the current expression evaluation context off the stack.
15130 ExprEvalContexts.pop_back();
15131
15132 // The global expression evaluation context record is never popped.
15133 ExprEvalContexts.back().NumTypos += NumTypos;
15134}
15135
15136void Sema::DiscardCleanupsInEvaluationContext() {
15137 ExprCleanupObjects.erase(
15138 ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects,
15139 ExprCleanupObjects.end());
15140 Cleanup.reset();
15141 MaybeODRUseExprs.clear();
15142}
15143
15144ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) {
15145 ExprResult Result = CheckPlaceholderExpr(E);
15146 if (Result.isInvalid())
15147 return ExprError();
15148 E = Result.get();
15149 if (!E->getType()->isVariablyModifiedType())
15150 return E;
15151 return TransformToPotentiallyEvaluated(E);
15152}
15153
15154/// Are we in a context that is potentially constant evaluated per C++20
15155/// [expr.const]p12?
15156static bool isPotentiallyConstantEvaluatedContext(Sema &SemaRef) {
15157 /// C++2a [expr.const]p12:
15158 // An expression or conversion is potentially constant evaluated if it is
15159 switch (SemaRef.ExprEvalContexts.back().Context) {
15160 case Sema::ExpressionEvaluationContext::ConstantEvaluated:
15161 // -- a manifestly constant-evaluated expression,
15162 case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
15163 case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
15164 case Sema::ExpressionEvaluationContext::DiscardedStatement:
15165 // -- a potentially-evaluated expression,
15166 case Sema::ExpressionEvaluationContext::UnevaluatedList:
15167 // -- an immediate subexpression of a braced-init-list,
15168
15169 // -- [FIXME] an expression of the form & cast-expression that occurs
15170 // within a templated entity
15171 // -- a subexpression of one of the above that is not a subexpression of
15172 // a nested unevaluated operand.
15173 return true;
15174
15175 case Sema::ExpressionEvaluationContext::Unevaluated:
15176 case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
15177 // Expressions in this context are never evaluated.
15178 return false;
15179 }
15180 llvm_unreachable("Invalid context");
15181}
15182
15183/// Return true if this function has a calling convention that requires mangling
15184/// in the size of the parameter pack.
15185static bool funcHasParameterSizeMangling(Sema &S, FunctionDecl *FD) {
15186 // These manglings don't do anything on non-Windows or non-x86 platforms, so
15187 // we don't need parameter type sizes.
15188 const llvm::Triple &TT = S.Context.getTargetInfo().getTriple();
15189 if (!TT.isOSWindows() || (TT.getArch() != llvm::Triple::x86 &&
15190 TT.getArch() != llvm::Triple::x86_64))
15191 return false;
15192
15193 // If this is C++ and this isn't an extern "C" function, parameters do not
15194 // need to be complete. In this case, C++ mangling will apply, which doesn't
15195 // use the size of the parameters.
15196 if (S.getLangOpts().CPlusPlus && !FD->isExternC())
15197 return false;
15198
15199 // Stdcall, fastcall, and vectorcall need this special treatment.
15200 CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
15201 switch (CC) {
15202 case CC_X86StdCall:
15203 case CC_X86FastCall:
15204 case CC_X86VectorCall:
15205 return true;
15206 default:
15207 break;
15208 }
15209 return false;
15210}
15211
15212/// Require that all of the parameter types of function be complete. Normally,
15213/// parameter types are only required to be complete when a function is called
15214/// or defined, but to mangle functions with certain calling conventions, the
15215/// mangler needs to know the size of the parameter list. In this situation,
15216/// MSVC doesn't emit an error or instantiate templates. Instead, MSVC mangles
15217/// the function as _foo@0, i.e. zero bytes of parameters, which will usually
15218/// result in a linker error. Clang doesn't implement this behavior, and instead
15219/// attempts to error at compile time.
15220static void CheckCompleteParameterTypesForMangler(Sema &S, FunctionDecl *FD,
15221 SourceLocation Loc) {
15222 class ParamIncompleteTypeDiagnoser : public Sema::TypeDiagnoser {
15223 FunctionDecl *FD;
15224 ParmVarDecl *Param;
15225
15226 public:
15227 ParamIncompleteTypeDiagnoser(FunctionDecl *FD, ParmVarDecl *Param)
15228 : FD(FD), Param(Param) {}
15229
15230 void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
15231 CallingConv CC = FD->getType()->castAs<FunctionType>()->getCallConv();
15232 StringRef CCName;
15233 switch (CC) {
15234 case CC_X86StdCall:
15235 CCName = "stdcall";
15236 break;
15237 case CC_X86FastCall:
15238 CCName = "fastcall";
15239 break;
15240 case CC_X86VectorCall:
15241 CCName = "vectorcall";
15242 break;
15243 default:
15244 llvm_unreachable("CC does not need mangling");
15245 }
15246
15247 S.Diag(Loc, diag::err_cconv_incomplete_param_type)
15248 << Param->getDeclName() << FD->getDeclName() << CCName;
15249 }
15250 };
15251
15252 for (ParmVarDecl *Param : FD->parameters()) {
15253 ParamIncompleteTypeDiagnoser Diagnoser(FD, Param);
15254 S.RequireCompleteType(Loc, Param->getType(), Diagnoser);
15255 }
15256}
15257
15258namespace {
15259enum class OdrUseContext {
15260 /// Declarations in this context are not odr-used.
15261 None,
15262 /// Declarations in this context are formally odr-used, but this is a
15263 /// dependent context.
15264 Dependent,
15265 /// Declarations in this context are odr-used but not actually used (yet).
15266 FormallyOdrUsed,
15267 /// Declarations in this context are used.
15268 Used
15269};
15270}
15271
15272/// Are we within a context in which references to resolved functions or to
15273/// variables result in odr-use?
15274static OdrUseContext isOdrUseContext(Sema &SemaRef) {
15275 OdrUseContext Result;
15276
15277 switch (SemaRef.ExprEvalContexts.back().Context) {
15278 case Sema::ExpressionEvaluationContext::Unevaluated:
15279 case Sema::ExpressionEvaluationContext::UnevaluatedList:
15280 case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
15281 return OdrUseContext::None;
15282
15283 case Sema::ExpressionEvaluationContext::ConstantEvaluated:
15284 case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
15285 Result = OdrUseContext::Used;
15286 break;
15287
15288 case Sema::ExpressionEvaluationContext::DiscardedStatement:
15289 Result = OdrUseContext::FormallyOdrUsed;
15290 break;
15291
15292 case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
15293 // A default argument formally results in odr-use, but doesn't actually
15294 // result in a use in any real sense until it itself is used.
15295 Result = OdrUseContext::FormallyOdrUsed;
15296 break;
15297 }
15298
15299 if (SemaRef.CurContext->isDependentContext())
15300 return OdrUseContext::Dependent;
15301
15302 return Result;
15303}
15304
15305static bool isImplicitlyDefinableConstexprFunction(FunctionDecl *Func) {
15306 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func);
15307 return Func->isConstexpr() &&
15308 (Func->isImplicitlyInstantiable() || (MD && !MD->isUserProvided()));
15309}
15310
15311/// Mark a function referenced, and check whether it is odr-used
15312/// (C++ [basic.def.odr]p2, C99 6.9p3)
15313void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
15314 bool MightBeOdrUse) {
15315 assert(Func && "No function?");
15316
15317 Func->setReferenced();
15318
15319 // Recursive functions aren't really used until they're used from some other
15320 // context.
15321 bool IsRecursiveCall = CurContext == Func;
15322
15323 // C++11 [basic.def.odr]p3:
15324 // A function whose name appears as a potentially-evaluated expression is
15325 // odr-used if it is the unique lookup result or the selected member of a
15326 // set of overloaded functions [...].
15327 //
15328 // We (incorrectly) mark overload resolution as an unevaluated context, so we
15329 // can just check that here.
15330 OdrUseContext OdrUse =
15331 MightBeOdrUse ? isOdrUseContext(*this) : OdrUseContext::None;
15332 if (IsRecursiveCall && OdrUse == OdrUseContext::Used)
15333 OdrUse = OdrUseContext::FormallyOdrUsed;
15334
15335 // C++20 [expr.const]p12:
15336 // A function [...] is needed for constant evaluation if it is [...] a
15337 // constexpr function that is named by an expression that is potentially
15338 // constant evaluated
15339 bool NeededForConstantEvaluation =
15340 isPotentiallyConstantEvaluatedContext(*this) &&
15341 isImplicitlyDefinableConstexprFunction(Func);
15342
15343 // Determine whether we require a function definition to exist, per
15344 // C++11 [temp.inst]p3:
15345 // Unless a function template specialization has been explicitly
15346 // instantiated or explicitly specialized, the function template
15347 // specialization is implicitly instantiated when the specialization is
15348 // referenced in a context that requires a function definition to exist.
15349 // C++20 [temp.inst]p7:
15350 // The existence of a definition of a [...] function is considered to
15351 // affect the semantics of the program if the [...] function is needed for
15352 // constant evaluation by an expression
15353 // C++20 [basic.def.odr]p10:
15354 // Every program shall contain exactly one definition of every non-inline
15355 // function or variable that is odr-used in that program outside of a
15356 // discarded statement
15357 // C++20 [special]p1:
15358 // The implementation will implicitly define [defaulted special members]
15359 // if they are odr-used or needed for constant evaluation.
15360 //
15361 // Note that we skip the implicit instantiation of templates that are only
15362 // used in unused default arguments or by recursive calls to themselves.
15363 // This is formally non-conforming, but seems reasonable in practice.
15364 bool NeedDefinition = !IsRecursiveCall && (OdrUse == OdrUseContext::Used ||
15365 NeededForConstantEvaluation);
15366
15367 // C++14 [temp.expl.spec]p6:
15368 // If a template [...] is explicitly specialized then that specialization
15369 // shall be declared before the first use of that specialization that would
15370 // cause an implicit instantiation to take place, in every translation unit
15371 // in which such a use occurs
15372 if (NeedDefinition &&
15373 (Func->getTemplateSpecializationKind() != TSK_Undeclared ||
15374 Func->getMemberSpecializationInfo()))
15375 checkSpecializationVisibility(Loc, Func);
15376
15377 // C++14 [except.spec]p17:
15378 // An exception-specification is considered to be needed when:
15379 // - the function is odr-used or, if it appears in an unevaluated operand,
15380 // would be odr-used if the expression were potentially-evaluated;
15381 //
15382 // Note, we do this even if MightBeOdrUse is false. That indicates that the
15383 // function is a pure virtual function we're calling, and in that case the
15384 // function was selected by overload resolution and we need to resolve its
15385 // exception specification for a different reason.
15386 const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>();
15387 if (FPT && isUnresolvedExceptionSpec(FPT->getExceptionSpecType()))
15388 ResolveExceptionSpec(Loc, FPT);
15389
15390 if (getLangOpts().CUDA)
15391 CheckCUDACall(Loc, Func);
15392
15393 // If we need a definition, try to create one.
15394 if (NeedDefinition && !Func->getBody()) {
15395 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) {
15396 Constructor = cast<CXXConstructorDecl>(Constructor->getFirstDecl());
15397 if (Constructor->isDefaulted() && !Constructor->isDeleted()) {
15398 if (Constructor->isDefaultConstructor()) {
15399 if (Constructor->isTrivial() &&
15400 !Constructor->hasAttr<DLLExportAttr>())
15401 return;
15402 DefineImplicitDefaultConstructor(Loc, Constructor);
15403 } else if (Constructor->isCopyConstructor()) {
15404 DefineImplicitCopyConstructor(Loc, Constructor);
15405 } else if (Constructor->isMoveConstructor()) {
15406 DefineImplicitMoveConstructor(Loc, Constructor);
15407 }
15408 } else if (Constructor->getInheritedConstructor()) {
15409 DefineInheritingConstructor(Loc, Constructor);
15410 }
15411 } else if (CXXDestructorDecl *Destructor =
15412 dyn_cast<CXXDestructorDecl>(Func)) {
15413 Destructor = cast<CXXDestructorDecl>(Destructor->getFirstDecl());
15414 if (Destructor->isDefaulted() && !Destructor->isDeleted()) {
15415 if (Destructor->isTrivial() && !Destructor->hasAttr<DLLExportAttr>())
15416 return;
15417 DefineImplicitDestructor(Loc, Destructor);
15418 }
15419 if (Destructor->isVirtual() && getLangOpts().AppleKext)
15420 MarkVTableUsed(Loc, Destructor->getParent());
15421 } else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) {
15422 if (MethodDecl->isOverloadedOperator() &&
15423 MethodDecl->getOverloadedOperator() == OO_Equal) {
15424 MethodDecl = cast<CXXMethodDecl>(MethodDecl->getFirstDecl());
15425 if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted()) {
15426 if (MethodDecl->isCopyAssignmentOperator())
15427 DefineImplicitCopyAssignment(Loc, MethodDecl);
15428 else if (MethodDecl->isMoveAssignmentOperator())
15429 DefineImplicitMoveAssignment(Loc, MethodDecl);
15430 }
15431 } else if (isa<CXXConversionDecl>(MethodDecl) &&
15432 MethodDecl->getParent()->isLambda()) {
15433 CXXConversionDecl *Conversion =
15434 cast<CXXConversionDecl>(MethodDecl->getFirstDecl());
15435 if (Conversion->isLambdaToBlockPointerConversion())
15436 DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion);
15437 else
15438 DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion);
15439 } else if (MethodDecl->isVirtual() && getLangOpts().AppleKext)
15440 MarkVTableUsed(Loc, MethodDecl->getParent());
15441 }
15442
15443 // Implicit instantiation of function templates and member functions of
15444 // class templates.
15445 if (Func->isImplicitlyInstantiable()) {
15446 TemplateSpecializationKind TSK =
15447 Func->getTemplateSpecializationKindForInstantiation();
15448 SourceLocation PointOfInstantiation = Func->getPointOfInstantiation();
15449 bool FirstInstantiation = PointOfInstantiation.isInvalid();
15450 if (FirstInstantiation) {
15451 PointOfInstantiation = Loc;
15452 Func->setTemplateSpecializationKind(TSK, PointOfInstantiation);
15453 } else if (TSK != TSK_ImplicitInstantiation) {
15454 // Use the point of use as the point of instantiation, instead of the
15455 // point of explicit instantiation (which we track as the actual point
15456 // of instantiation). This gives better backtraces in diagnostics.
15457 PointOfInstantiation = Loc;
15458 }
15459
15460 if (FirstInstantiation || TSK != TSK_ImplicitInstantiation ||
15461 Func->isConstexpr()) {
15462 if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
15463 cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
15464 CodeSynthesisContexts.size())
15465 PendingLocalImplicitInstantiations.push_back(
15466 std::make_pair(Func, PointOfInstantiation));
15467 else if (Func->isConstexpr())
15468 // Do not defer instantiations of constexpr functions, to avoid the
15469 // expression evaluator needing to call back into Sema if it sees a
15470 // call to such a function.
15471 InstantiateFunctionDefinition(PointOfInstantiation, Func);
15472 else {
15473 Func->setInstantiationIsPending(true);
15474 PendingInstantiations.push_back(
15475 std::make_pair(Func, PointOfInstantiation));
15476 // Notify the consumer that a function was implicitly instantiated.
15477 Consumer.HandleCXXImplicitFunctionInstantiation(Func);
15478 }
15479 }
15480 } else {
15481 // Walk redefinitions, as some of them may be instantiable.
15482 for (auto i : Func->redecls()) {
15483 if (!i->isUsed(false) && i->isImplicitlyInstantiable())
15484 MarkFunctionReferenced(Loc, i, MightBeOdrUse);
15485 }
15486 }
15487 }
15488
15489 // If this is the first "real" use, act on that.
15490 if (OdrUse == OdrUseContext::Used && !Func->isUsed(/*CheckUsedAttr=*/false)) {
15491 // Keep track of used but undefined functions.
15492 if (!Func->isDefined()) {
15493 if (mightHaveNonExternalLinkage(Func))
15494 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
15495 else if (Func->getMostRecentDecl()->isInlined() &&
15496 !LangOpts.GNUInline &&
15497 !Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>())
15498 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
15499 else if (isExternalWithNoLinkageType(Func))
15500 UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
15501 }
15502
15503 // Some x86 Windows calling conventions mangle the size of the parameter
15504 // pack into the name. Computing the size of the parameters requires the
15505 // parameter types to be complete. Check that now.
15506 if (funcHasParameterSizeMangling(*this, Func))
15507 CheckCompleteParameterTypesForMangler(*this, Func, Loc);
15508
15509 Func->markUsed(Context);
15510
15511 if (LangOpts.OpenMP && LangOpts.OpenMPIsDevice)
15512 checkOpenMPDeviceFunction(Loc, Func);
15513 }
15514}
15515
15516/// Directly mark a variable odr-used. Given a choice, prefer to use
15517/// MarkVariableReferenced since it does additional checks and then
15518/// calls MarkVarDeclODRUsed.
15519/// If the variable must be captured:
15520/// - if FunctionScopeIndexToStopAt is null, capture it in the CurContext
15521/// - else capture it in the DeclContext that maps to the
15522/// *FunctionScopeIndexToStopAt on the FunctionScopeInfo stack.
15523static void
15524MarkVarDeclODRUsed(VarDecl *Var, SourceLocation Loc, Sema &SemaRef,
15525 const unsigned *const FunctionScopeIndexToStopAt = nullptr) {
15526 // Keep track of used but undefined variables.
15527 // FIXME: We shouldn't suppress this warning for static data members.
15528 if (Var->hasDefinition(SemaRef.Context) == VarDecl::DeclarationOnly &&
15529 (!Var->isExternallyVisible() || Var->isInline() ||
15530 SemaRef.isExternalWithNoLinkageType(Var)) &&
15531 !(Var->isStaticDataMember() && Var->hasInit())) {
15532 SourceLocation &old = SemaRef.UndefinedButUsed[Var->getCanonicalDecl()];
15533 if (old.isInvalid())
15534 old = Loc;
15535 }
15536 QualType CaptureType, DeclRefType;
15537 SemaRef.tryCaptureVariable(Var, Loc, Sema::TryCapture_Implicit,
15538 /*EllipsisLoc*/ SourceLocation(),
15539 /*BuildAndDiagnose*/ true,
15540 CaptureType, DeclRefType,
15541 FunctionScopeIndexToStopAt);
15542
15543 Var->markUsed(SemaRef.Context);
15544}
15545
15546void Sema::MarkCaptureUsedInEnclosingContext(VarDecl *Capture,
15547 SourceLocation Loc,
15548 unsigned CapturingScopeIndex) {
15549 MarkVarDeclODRUsed(Capture, Loc, *this, &CapturingScopeIndex);
15550}
15551
15552static void
15553diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
15554 ValueDecl *var, DeclContext *DC) {
15555 DeclContext *VarDC = var->getDeclContext();
15556
15557 // If the parameter still belongs to the translation unit, then
15558 // we're actually just using one parameter in the declaration of
15559 // the next.
15560 if (isa<ParmVarDecl>(var) &&
15561 isa<TranslationUnitDecl>(VarDC))
15562 return;
15563
15564 // For C code, don't diagnose about capture if we're not actually in code
15565 // right now; it's impossible to write a non-constant expression outside of
15566 // function context, so we'll get other (more useful) diagnostics later.
15567 //
15568 // For C++, things get a bit more nasty... it would be nice to suppress this
15569 // diagnostic for certain cases like using a local variable in an array bound
15570 // for a member of a local class, but the correct predicate is not obvious.
15571 if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod())
15572 return;
15573
15574 unsigned ValueKind = isa<BindingDecl>(var) ? 1 : 0;
15575 unsigned ContextKind = 3; // unknown
15576 if (isa<CXXMethodDecl>(VarDC) &&
15577 cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) {
15578 ContextKind = 2;
15579 } else if (isa<FunctionDecl>(VarDC)) {
15580 ContextKind = 0;
15581 } else if (isa<BlockDecl>(VarDC)) {
15582 ContextKind = 1;
15583 }
15584
15585 S.Diag(loc, diag::err_reference_to_local_in_enclosing_context)
15586 << var << ValueKind << ContextKind << VarDC;
15587 S.Diag(var->getLocation(), diag::note_entity_declared_at)
15588 << var;
15589
15590 // FIXME: Add additional diagnostic info about class etc. which prevents
15591 // capture.
15592}
15593
15594
15595static bool isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo *CSI, VarDecl *Var,
15596 bool &SubCapturesAreNested,
15597 QualType &CaptureType,
15598 QualType &DeclRefType) {
15599 // Check whether we've already captured it.
15600 if (CSI->CaptureMap.count(Var)) {
15601 // If we found a capture, any subcaptures are nested.
15602 SubCapturesAreNested = true;
15603
15604 // Retrieve the capture type for this variable.
15605 CaptureType = CSI->getCapture(Var).getCaptureType();
15606
15607 // Compute the type of an expression that refers to this variable.
15608 DeclRefType = CaptureType.getNonReferenceType();
15609
15610 // Similarly to mutable captures in lambda, all the OpenMP captures by copy
15611 // are mutable in the sense that user can change their value - they are
15612 // private instances of the captured declarations.
15613 const Capture &Cap = CSI->getCapture(Var);
15614 if (Cap.isCopyCapture() &&
15615 !(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable) &&
15616 !(isa<CapturedRegionScopeInfo>(CSI) &&
15617 cast<CapturedRegionScopeInfo>(CSI)->CapRegionKind == CR_OpenMP))
15618 DeclRefType.addConst();
15619 return true;
15620 }
15621 return false;
15622}
15623
15624// Only block literals, captured statements, and lambda expressions can
15625// capture; other scopes don't work.
15626static DeclContext *getParentOfCapturingContextOrNull(DeclContext *DC, VarDecl *Var,
15627 SourceLocation Loc,
15628 const bool Diagnose, Sema &S) {
15629 if (isa<BlockDecl>(DC) || isa<CapturedDecl>(DC) || isLambdaCallOperator(DC))
15630 return getLambdaAwareParentOfDeclContext(DC);
15631 else if (Var->hasLocalStorage()) {
15632 if (Diagnose)
15633 diagnoseUncapturableValueReference(S, Loc, Var, DC);
15634 }
15635 return nullptr;
15636}
15637
15638// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
15639// certain types of variables (unnamed, variably modified types etc.)
15640// so check for eligibility.
15641static bool isVariableCapturable(CapturingScopeInfo *CSI, VarDecl *Var,
15642 SourceLocation Loc,
15643 const bool Diagnose, Sema &S) {
15644
15645 bool IsBlock = isa<BlockScopeInfo>(CSI);
15646 bool IsLambda = isa<LambdaScopeInfo>(CSI);
15647
15648 // Lambdas are not allowed to capture unnamed variables
15649 // (e.g. anonymous unions).
15650 // FIXME: The C++11 rule don't actually state this explicitly, but I'm
15651 // assuming that's the intent.
15652 if (IsLambda && !Var->getDeclName()) {
15653 if (Diagnose) {
15654 S.Diag(Loc, diag::err_lambda_capture_anonymous_var);
15655 S.Diag(Var->getLocation(), diag::note_declared_at);
15656 }
15657 return false;
15658 }
15659
15660 // Prohibit variably-modified types in blocks; they're difficult to deal with.
15661 if (Var->getType()->isVariablyModifiedType() && IsBlock) {
15662 if (Diagnose) {
15663 S.Diag(Loc, diag::err_ref_vm_type);
15664 S.Diag(Var->getLocation(), diag::note_previous_decl)
15665 << Var->getDeclName();
15666 }
15667 return false;
15668 }
15669 // Prohibit structs with flexible array members too.
15670 // We cannot capture what is in the tail end of the struct.
15671 if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) {
15672 if (VTTy->getDecl()->hasFlexibleArrayMember()) {
15673 if (Diagnose) {
15674 if (IsBlock)
15675 S.Diag(Loc, diag::err_ref_flexarray_type);
15676 else
15677 S.Diag(Loc, diag::err_lambda_capture_flexarray_type)
15678 << Var->getDeclName();
15679 S.Diag(Var->getLocation(), diag::note_previous_decl)
15680 << Var->getDeclName();
15681 }
15682 return false;
15683 }
15684 }
15685 const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
15686 // Lambdas and captured statements are not allowed to capture __block
15687 // variables; they don't support the expected semantics.
15688 if (HasBlocksAttr && (IsLambda || isa<CapturedRegionScopeInfo>(CSI))) {
15689 if (Diagnose) {
15690 S.Diag(Loc, diag::err_capture_block_variable)
15691 << Var->getDeclName() << !IsLambda;
15692 S.Diag(Var->getLocation(), diag::note_previous_decl)
15693 << Var->getDeclName();
15694 }
15695 return false;
15696 }
15697 // OpenCL v2.0 s6.12.5: Blocks cannot reference/capture other blocks
15698 if (S.getLangOpts().OpenCL && IsBlock &&
15699 Var->getType()->isBlockPointerType()) {
15700 if (Diagnose)
15701 S.Diag(Loc, diag::err_opencl_block_ref_block);
15702 return false;
15703 }
15704
15705 return true;
15706}
15707
15708// Returns true if the capture by block was successful.
15709static bool captureInBlock(BlockScopeInfo *BSI, VarDecl *Var,
15710 SourceLocation Loc,
15711 const bool BuildAndDiagnose,
15712 QualType &CaptureType,
15713 QualType &DeclRefType,
15714 const bool Nested,
15715 Sema &S, bool Invalid) {
15716 bool ByRef = false;
15717
15718 // Blocks are not allowed to capture arrays, excepting OpenCL.
15719 // OpenCL v2.0 s1.12.5 (revision 40): arrays are captured by reference
15720 // (decayed to pointers).
15721 if (!Invalid && !S.getLangOpts().OpenCL && CaptureType->isArrayType()) {
15722 if (BuildAndDiagnose) {
15723 S.Diag(Loc, diag::err_ref_array_type);
15724 S.Diag(Var->getLocation(), diag::note_previous_decl)
15725 << Var->getDeclName();
15726 Invalid = true;
15727 } else {
15728 return false;
15729 }
15730 }
15731
15732 // Forbid the block-capture of autoreleasing variables.
15733 if (!Invalid &&
15734 CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
15735 if (BuildAndDiagnose) {
15736 S.Diag(Loc, diag::err_arc_autoreleasing_capture)
15737 << /*block*/ 0;
15738 S.Diag(Var->getLocation(), diag::note_previous_decl)
15739 << Var->getDeclName();
15740 Invalid = true;
15741 } else {
15742 return false;
15743 }
15744 }
15745
15746 // Warn about implicitly autoreleasing indirect parameters captured by blocks.
15747 if (const auto *PT = CaptureType->getAs<PointerType>()) {
15748 // This function finds out whether there is an AttributedType of kind
15749 // attr::ObjCOwnership in Ty. The existence of AttributedType of kind
15750 // attr::ObjCOwnership implies __autoreleasing was explicitly specified
15751 // rather than being added implicitly by the compiler.
15752 auto IsObjCOwnershipAttributedType = [](QualType Ty) {
15753 while (const auto *AttrTy = Ty->getAs<AttributedType>()) {
15754 if (AttrTy->getAttrKind() == attr::ObjCOwnership)
15755 return true;
15756
15757 // Peel off AttributedTypes that are not of kind ObjCOwnership.
15758 Ty = AttrTy->getModifiedType();
15759 }
15760
15761 return false;
15762 };
15763
15764 QualType PointeeTy = PT->getPointeeType();
15765
15766 if (!Invalid && PointeeTy->getAs<ObjCObjectPointerType>() &&
15767 PointeeTy.getObjCLifetime() == Qualifiers::OCL_Autoreleasing &&
15768 !IsObjCOwnershipAttributedType(PointeeTy)) {
15769 if (BuildAndDiagnose) {
15770 SourceLocation VarLoc = Var->getLocation();
15771 S.Diag(Loc, diag::warn_block_capture_autoreleasing);
15772 S.Diag(VarLoc, diag::note_declare_parameter_strong);
15773 }
15774 }
15775 }
15776
15777 const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
15778 if (HasBlocksAttr || CaptureType->isReferenceType() ||
15779 (S.getLangOpts().OpenMP && S.isOpenMPCapturedDecl(Var))) {
15780 // Block capture by reference does not change the capture or
15781 // declaration reference types.
15782 ByRef = true;
15783 } else {
15784 // Block capture by copy introduces 'const'.
15785 CaptureType = CaptureType.getNonReferenceType().withConst();
15786 DeclRefType = CaptureType;
15787 }
15788
15789 // Actually capture the variable.
15790 if (BuildAndDiagnose)
15791 BSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc, SourceLocation(),
15792 CaptureType, Invalid);
15793
15794 return !Invalid;
15795}
15796
15797
15798/// Capture the given variable in the captured region.
15799static bool captureInCapturedRegion(CapturedRegionScopeInfo *RSI,
15800 VarDecl *Var,
15801 SourceLocation Loc,
15802 const bool BuildAndDiagnose,
15803 QualType &CaptureType,
15804 QualType &DeclRefType,
15805 const bool RefersToCapturedVariable,
15806 Sema &S, bool Invalid) {
15807 // By default, capture variables by reference.
15808 bool ByRef = true;
15809 // Using an LValue reference type is consistent with Lambdas (see below).
15810 if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP) {
15811 if (S.isOpenMPCapturedDecl(Var)) {
15812 bool HasConst = DeclRefType.isConstQualified();
15813 DeclRefType = DeclRefType.getUnqualifiedType();
15814 // Don't lose diagnostics about assignments to const.
15815 if (HasConst)
15816 DeclRefType.addConst();
15817 }
15818 ByRef = S.isOpenMPCapturedByRef(Var, RSI->OpenMPLevel);
15819 }
15820
15821 if (ByRef)
15822 CaptureType = S.Context.getLValueReferenceType(DeclRefType);
15823 else
15824 CaptureType = DeclRefType;
15825
15826 // Actually capture the variable.
15827 if (BuildAndDiagnose)
15828 RSI->addCapture(Var, /*isBlock*/ false, ByRef, RefersToCapturedVariable,
15829 Loc, SourceLocation(), CaptureType, Invalid);
15830
15831 return !Invalid;
15832}
15833
15834/// Capture the given variable in the lambda.
15835static bool captureInLambda(LambdaScopeInfo *LSI,
15836 VarDecl *Var,
15837 SourceLocation Loc,
15838 const bool BuildAndDiagnose,
15839 QualType &CaptureType,
15840 QualType &DeclRefType,
15841 const bool RefersToCapturedVariable,
15842 const Sema::TryCaptureKind Kind,
15843 SourceLocation EllipsisLoc,
15844 const bool IsTopScope,
15845 Sema &S, bool Invalid) {
15846 // Determine whether we are capturing by reference or by value.
15847 bool ByRef = false;
15848 if (IsTopScope && Kind != Sema::TryCapture_Implicit) {
15849 ByRef = (Kind == Sema::TryCapture_ExplicitByRef);
15850 } else {
15851 ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref);
15852 }
15853
15854 // Compute the type of the field that will capture this variable.
15855 if (ByRef) {
15856 // C++11 [expr.prim.lambda]p15:
15857 // An entity is captured by reference if it is implicitly or
15858 // explicitly captured but not captured by copy. It is
15859 // unspecified whether additional unnamed non-static data
15860 // members are declared in the closure type for entities
15861 // captured by reference.
15862 //
15863 // FIXME: It is not clear whether we want to build an lvalue reference
15864 // to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears
15865 // to do the former, while EDG does the latter. Core issue 1249 will
15866 // clarify, but for now we follow GCC because it's a more permissive and
15867 // easily defensible position.
15868 CaptureType = S.Context.getLValueReferenceType(DeclRefType);
15869 } else {
15870 // C++11 [expr.prim.lambda]p14:
15871 // For each entity captured by copy, an unnamed non-static
15872 // data member is declared in the closure type. The
15873 // declaration order of these members is unspecified. The type
15874 // of such a data member is the type of the corresponding
15875 // captured entity if the entity is not a reference to an
15876 // object, or the referenced type otherwise. [Note: If the
15877 // captured entity is a reference to a function, the
15878 // corresponding data member is also a reference to a
15879 // function. - end note ]
15880 if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){
15881 if (!RefType->getPointeeType()->isFunctionType())
15882 CaptureType = RefType->getPointeeType();
15883 }
15884
15885 // Forbid the lambda copy-capture of autoreleasing variables.
15886 if (!Invalid &&
15887 CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
15888 if (BuildAndDiagnose) {
15889 S.Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1;
15890 S.Diag(Var->getLocation(), diag::note_previous_decl)
15891 << Var->getDeclName();
15892 Invalid = true;
15893 } else {
15894 return false;
15895 }
15896 }
15897
15898 // Make sure that by-copy captures are of a complete and non-abstract type.
15899 if (!Invalid && BuildAndDiagnose) {
15900 if (!CaptureType->isDependentType() &&
15901 S.RequireCompleteType(Loc, CaptureType,
15902 diag::err_capture_of_incomplete_type,
15903 Var->getDeclName()))
15904 Invalid = true;
15905 else if (S.RequireNonAbstractType(Loc, CaptureType,
15906 diag::err_capture_of_abstract_type))
15907 Invalid = true;
15908 }
15909 }
15910
15911 // Compute the type of a reference to this captured variable.
15912 if (ByRef)
15913 DeclRefType = CaptureType.getNonReferenceType();
15914 else {
15915 // C++ [expr.prim.lambda]p5:
15916 // The closure type for a lambda-expression has a public inline
15917 // function call operator [...]. This function call operator is
15918 // declared const (9.3.1) if and only if the lambda-expression's
15919 // parameter-declaration-clause is not followed by mutable.
15920 DeclRefType = CaptureType.getNonReferenceType();
15921 if (!LSI->Mutable && !CaptureType->isReferenceType())
15922 DeclRefType.addConst();
15923 }
15924
15925 // Add the capture.
15926 if (BuildAndDiagnose)
15927 LSI->addCapture(Var, /*IsBlock=*/false, ByRef, RefersToCapturedVariable,
15928 Loc, EllipsisLoc, CaptureType, Invalid);
15929
15930 return !Invalid;
15931}
15932
15933bool Sema::tryCaptureVariable(
15934 VarDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind,
15935 SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType,
15936 QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt) {
15937 // An init-capture is notionally from the context surrounding its
15938 // declaration, but its parent DC is the lambda class.
15939 DeclContext *VarDC = Var->getDeclContext();
15940 if (Var->isInitCapture())
15941 VarDC = VarDC->getParent();
15942
15943 DeclContext *DC = CurContext;
15944 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
15945 ? *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
15946 // We need to sync up the Declaration Context with the
15947 // FunctionScopeIndexToStopAt
15948 if (FunctionScopeIndexToStopAt) {
15949 unsigned FSIndex = FunctionScopes.size() - 1;
15950 while (FSIndex != MaxFunctionScopesIndex) {
15951 DC = getLambdaAwareParentOfDeclContext(DC);
15952 --FSIndex;
15953 }
15954 }
15955
15956
15957 // If the variable is declared in the current context, there is no need to
15958 // capture it.
15959 if (VarDC == DC) return true;
15960
15961 // Capture global variables if it is required to use private copy of this
15962 // variable.
15963 bool IsGlobal = !Var->hasLocalStorage();
15964 if (IsGlobal &&
15965 !(LangOpts.OpenMP && isOpenMPCapturedDecl(Var, /*CheckScopeInfo=*/true,
15966 MaxFunctionScopesIndex)))
15967 return true;
15968 Var = Var->getCanonicalDecl();
15969
15970 // Walk up the stack to determine whether we can capture the variable,
15971 // performing the "simple" checks that don't depend on type. We stop when
15972 // we've either hit the declared scope of the variable or find an existing
15973 // capture of that variable. We start from the innermost capturing-entity
15974 // (the DC) and ensure that all intervening capturing-entities
15975 // (blocks/lambdas etc.) between the innermost capturer and the variable`s
15976 // declcontext can either capture the variable or have already captured
15977 // the variable.
15978 CaptureType = Var->getType();
15979 DeclRefType = CaptureType.getNonReferenceType();
15980 bool Nested = false;
15981 bool Explicit = (Kind != TryCapture_Implicit);
15982 unsigned FunctionScopesIndex = MaxFunctionScopesIndex;
15983 do {
15984 // Only block literals, captured statements, and lambda expressions can
15985 // capture; other scopes don't work.
15986 DeclContext *ParentDC = getParentOfCapturingContextOrNull(DC, Var,
15987 ExprLoc,
15988 BuildAndDiagnose,
15989 *this);
15990 // We need to check for the parent *first* because, if we *have*
15991 // private-captured a global variable, we need to recursively capture it in
15992 // intermediate blocks, lambdas, etc.
15993 if (!ParentDC) {
15994 if (IsGlobal) {
15995 FunctionScopesIndex = MaxFunctionScopesIndex - 1;
15996 break;
15997 }
15998 return true;
15999 }
16000
16001 FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex];
16002 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FSI);
16003
16004
16005 // Check whether we've already captured it.
16006 if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, Nested, CaptureType,
16007 DeclRefType)) {
16008 CSI->getCapture(Var).markUsed(BuildAndDiagnose);
16009 break;
16010 }
16011 // If we are instantiating a generic lambda call operator body,
16012 // we do not want to capture new variables. What was captured
16013 // during either a lambdas transformation or initial parsing
16014 // should be used.
16015 if (isGenericLambdaCallOperatorSpecialization(DC)) {
16016 if (BuildAndDiagnose) {
16017 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
16018 if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) {
16019 Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
16020 Diag(Var->getLocation(), diag::note_previous_decl)
16021 << Var->getDeclName();
16022 Diag(LSI->Lambda->getBeginLoc(), diag::note_lambda_decl);
16023 } else
16024 diagnoseUncapturableValueReference(*this, ExprLoc, Var, DC);
16025 }
16026 return true;
16027 }
16028
16029 // Try to capture variable-length arrays types.
16030 if (Var->getType()->isVariablyModifiedType()) {
16031 // We're going to walk down into the type and look for VLA
16032 // expressions.
16033 QualType QTy = Var->getType();
16034 if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Var))
16035 QTy = PVD->getOriginalType();
16036 captureVariablyModifiedType(Context, QTy, CSI);
16037 }
16038
16039 if (getLangOpts().OpenMP) {
16040 if (auto *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
16041 // OpenMP private variables should not be captured in outer scope, so
16042 // just break here. Similarly, global variables that are captured in a
16043 // target region should not be captured outside the scope of the region.
16044 if (RSI->CapRegionKind == CR_OpenMP) {
16045 bool IsOpenMPPrivateDecl = isOpenMPPrivateDecl(Var, RSI->OpenMPLevel);
16046 auto IsTargetCap = !IsOpenMPPrivateDecl &&
16047 isOpenMPTargetCapturedDecl(Var, RSI->OpenMPLevel);
16048 // When we detect target captures we are looking from inside the
16049 // target region, therefore we need to propagate the capture from the
16050 // enclosing region. Therefore, the capture is not initially nested.
16051 if (IsTargetCap)
16052 adjustOpenMPTargetScopeIndex(FunctionScopesIndex, RSI->OpenMPLevel);
16053
16054 if (IsTargetCap || IsOpenMPPrivateDecl) {
16055 Nested = !IsTargetCap;
16056 DeclRefType = DeclRefType.getUnqualifiedType();
16057 CaptureType = Context.getLValueReferenceType(DeclRefType);
16058 break;
16059 }
16060 }
16061 }
16062 }
16063 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) {
16064 // No capture-default, and this is not an explicit capture
16065 // so cannot capture this variable.
16066 if (BuildAndDiagnose) {
16067 Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
16068 Diag(Var->getLocation(), diag::note_previous_decl)
16069 << Var->getDeclName();
16070 if (cast<LambdaScopeInfo>(CSI)->Lambda)
16071 Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getBeginLoc(),
16072 diag::note_lambda_decl);
16073 // FIXME: If we error out because an outer lambda can not implicitly
16074 // capture a variable that an inner lambda explicitly captures, we
16075 // should have the inner lambda do the explicit capture - because
16076 // it makes for cleaner diagnostics later. This would purely be done
16077 // so that the diagnostic does not misleadingly claim that a variable
16078 // can not be captured by a lambda implicitly even though it is captured
16079 // explicitly. Suggestion:
16080 // - create const bool VariableCaptureWasInitiallyExplicit = Explicit
16081 // at the function head
16082 // - cache the StartingDeclContext - this must be a lambda
16083 // - captureInLambda in the innermost lambda the variable.
16084 }
16085 return true;
16086 }
16087
16088 FunctionScopesIndex--;
16089 DC = ParentDC;
16090 Explicit = false;
16091 } while (!VarDC->Equals(DC));
16092
16093 // Walk back down the scope stack, (e.g. from outer lambda to inner lambda)
16094 // computing the type of the capture at each step, checking type-specific
16095 // requirements, and adding captures if requested.
16096 // If the variable had already been captured previously, we start capturing
16097 // at the lambda nested within that one.
16098 bool Invalid = false;
16099 for (unsigned I = ++FunctionScopesIndex, N = MaxFunctionScopesIndex + 1; I != N;
16100 ++I) {
16101 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]);
16102
16103 // Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
16104 // certain types of variables (unnamed, variably modified types etc.)
16105 // so check for eligibility.
16106 if (!Invalid)
16107 Invalid =
16108 !isVariableCapturable(CSI, Var, ExprLoc, BuildAndDiagnose, *this);
16109
16110 // After encountering an error, if we're actually supposed to capture, keep
16111 // capturing in nested contexts to suppress any follow-on diagnostics.
16112 if (Invalid && !BuildAndDiagnose)
16113 return true;
16114
16115 if (BlockScopeInfo *BSI = dyn_cast<BlockScopeInfo>(CSI)) {
16116 Invalid = !captureInBlock(BSI, Var, ExprLoc, BuildAndDiagnose, CaptureType,
16117 DeclRefType, Nested, *this, Invalid);
16118 Nested = true;
16119 } else if (CapturedRegionScopeInfo *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
16120 Invalid = !captureInCapturedRegion(RSI, Var, ExprLoc, BuildAndDiagnose,
16121 CaptureType, DeclRefType, Nested,
16122 *this, Invalid);
16123 Nested = true;
16124 } else {
16125 LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
16126 Invalid =
16127 !captureInLambda(LSI, Var, ExprLoc, BuildAndDiagnose, CaptureType,
16128 DeclRefType, Nested, Kind, EllipsisLoc,
16129 /*IsTopScope*/ I == N - 1, *this, Invalid);
16130 Nested = true;
16131 }
16132
16133 if (Invalid && !BuildAndDiagnose)
16134 return true;
16135 }
16136 return Invalid;
16137}
16138
16139bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
16140 TryCaptureKind Kind, SourceLocation EllipsisLoc) {
16141 QualType CaptureType;
16142 QualType DeclRefType;
16143 return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc,
16144 /*BuildAndDiagnose=*/true, CaptureType,
16145 DeclRefType, nullptr);
16146}
16147
16148bool Sema::NeedToCaptureVariable(VarDecl *Var, SourceLocation Loc) {
16149 QualType CaptureType;
16150 QualType DeclRefType;
16151 return !tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
16152 /*BuildAndDiagnose=*/false, CaptureType,
16153 DeclRefType, nullptr);
16154}
16155
16156QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) {
16157 QualType CaptureType;
16158 QualType DeclRefType;
16159
16160 // Determine whether we can capture this variable.
16161 if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
16162 /*BuildAndDiagnose=*/false, CaptureType,
16163 DeclRefType, nullptr))
16164 return QualType();
16165
16166 return DeclRefType;
16167}
16168
16169/// Walk the set of potential results of an expression and mark them all as
16170/// non-odr-uses if they satisfy the side-conditions of the NonOdrUseReason.
16171///
16172/// \return A new expression if we found any potential results, ExprEmpty() if
16173/// not, and ExprError() if we diagnosed an error.
16174static ExprResult rebuildPotentialResultsAsNonOdrUsed(Sema &S, Expr *E,
16175 NonOdrUseReason NOUR) {
16176 // Per C++11 [basic.def.odr], a variable is odr-used "unless it is
16177 // an object that satisfies the requirements for appearing in a
16178 // constant expression (5.19) and the lvalue-to-rvalue conversion (4.1)
16179 // is immediately applied." This function handles the lvalue-to-rvalue
16180 // conversion part.
16181 //
16182 // If we encounter a node that claims to be an odr-use but shouldn't be, we
16183 // transform it into the relevant kind of non-odr-use node and rebuild the
16184 // tree of nodes leading to it.
16185 //
16186 // This is a mini-TreeTransform that only transforms a restricted subset of
16187 // nodes (and only certain operands of them).
16188
16189 // Rebuild a subexpression.
16190 auto Rebuild = [&](Expr *Sub) {
16191 return rebuildPotentialResultsAsNonOdrUsed(S, Sub, NOUR);
16192 };
16193
16194 // Check whether a potential result satisfies the requirements of NOUR.
16195 auto IsPotentialResultOdrUsed = [&](NamedDecl *D) {
16196 // Any entity other than a VarDecl is always odr-used whenever it's named
16197 // in a potentially-evaluated expression.
16198 auto *VD = dyn_cast<VarDecl>(D);
16199 if (!VD)
16200 return true;
16201
16202 // C++2a [basic.def.odr]p4:
16203 // A variable x whose name appears as a potentially-evalauted expression
16204 // e is odr-used by e unless
16205 // -- x is a reference that is usable in constant expressions, or
16206 // -- x is a variable of non-reference type that is usable in constant
16207 // expressions and has no mutable subobjects, and e is an element of
16208 // the set of potential results of an expression of
16209 // non-volatile-qualified non-class type to which the lvalue-to-rvalue
16210 // conversion is applied, or
16211 // -- x is a variable of non-reference type, and e is an element of the
16212 // set of potential results of a discarded-value expression to which
16213 // the lvalue-to-rvalue conversion is not applied
16214 //
16215 // We check the first bullet and the "potentially-evaluated" condition in
16216 // BuildDeclRefExpr. We check the type requirements in the second bullet
16217 // in CheckLValueToRValueConversionOperand below.
16218 switch (NOUR) {
16219 case NOUR_None:
16220 case NOUR_Unevaluated:
16221 llvm_unreachable("unexpected non-odr-use-reason");
16222
16223 case NOUR_Constant:
16224 // Constant references were handled when they were built.
16225 if (VD->getType()->isReferenceType())
16226 return true;
16227 if (auto *RD = VD->getType()->getAsCXXRecordDecl())
16228 if (RD->hasMutableFields())
16229 return true;
16230 if (!VD->isUsableInConstantExpressions(S.Context))
16231 return true;
16232 break;
16233
16234 case NOUR_Discarded:
16235 if (VD->getType()->isReferenceType())
16236 return true;
16237 break;
16238 }
16239 return false;
16240 };
16241
16242 // Mark that this expression does not constitute an odr-use.
16243 auto MarkNotOdrUsed = [&] {
16244 S.MaybeODRUseExprs.erase(E);
16245 if (LambdaScopeInfo *LSI = S.getCurLambda())
16246 LSI->markVariableExprAsNonODRUsed(E);
16247 };
16248
16249 // C++2a [basic.def.odr]p2:
16250 // The set of potential results of an expression e is defined as follows:
16251 switch (E->getStmtClass()) {
16252 // -- If e is an id-expression, ...
16253 case Expr::DeclRefExprClass: {
16254 auto *DRE = cast<DeclRefExpr>(E);
16255 if (DRE->isNonOdrUse() || IsPotentialResultOdrUsed(DRE->getDecl()))
16256 break;
16257
16258 // Rebuild as a non-odr-use DeclRefExpr.
16259 MarkNotOdrUsed();
16260 TemplateArgumentListInfo TemplateArgStorage, *TemplateArgs = nullptr;
16261 if (DRE->hasExplicitTemplateArgs()) {
16262 DRE->copyTemplateArgumentsInto(TemplateArgStorage);
16263 TemplateArgs = &TemplateArgStorage;
16264 }
16265 return DeclRefExpr::Create(
16266 S.Context, DRE->getQualifierLoc(), DRE->getTemplateKeywordLoc(),
16267 DRE->getDecl(), DRE->refersToEnclosingVariableOrCapture(),
16268 DRE->getNameInfo(), DRE->getType(), DRE->getValueKind(),
16269 DRE->getFoundDecl(), TemplateArgs, NOUR);
16270 }
16271
16272 case Expr::FunctionParmPackExprClass: {
16273 auto *FPPE = cast<FunctionParmPackExpr>(E);
16274 // If any of the declarations in the pack is odr-used, then the expression
16275 // as a whole constitutes an odr-use.
16276 for (VarDecl *D : *FPPE)
16277 if (IsPotentialResultOdrUsed(D))
16278 return ExprEmpty();
16279
16280 // FIXME: Rebuild as a non-odr-use FunctionParmPackExpr? In practice,
16281 // nothing cares about whether we marked this as an odr-use, but it might
16282 // be useful for non-compiler tools.
16283 MarkNotOdrUsed();
16284 break;
16285 }
16286
16287 // FIXME: Implement these.
16288 // -- If e is a subscripting operation with an array operand...
16289 // -- If e is a class member access expression [...] naming a non-static
16290 // data member...
16291
16292 // -- If e is a class member access expression naming a static data member,
16293 // ...
16294 case Expr::MemberExprClass: {
16295 auto *ME = cast<MemberExpr>(E);
16296 if (ME->getMemberDecl()->isCXXInstanceMember())
16297 // FIXME: Recurse to the left-hand side.
16298 break;
16299
16300 if (ME->isNonOdrUse() || IsPotentialResultOdrUsed(ME->getMemberDecl()))
16301 break;
16302
16303 // Rebuild as a non-odr-use MemberExpr.
16304 MarkNotOdrUsed();
16305 TemplateArgumentListInfo TemplateArgStorage, *TemplateArgs = nullptr;
16306 if (ME->hasExplicitTemplateArgs()) {
16307 ME->copyTemplateArgumentsInto(TemplateArgStorage);
16308 TemplateArgs = &TemplateArgStorage;
16309 }
16310 return MemberExpr::Create(
16311 S.Context, ME->getBase(), ME->isArrow(), ME->getOperatorLoc(),
16312 ME->getQualifierLoc(), ME->getTemplateKeywordLoc(), ME->getMemberDecl(),
16313 ME->getFoundDecl(), ME->getMemberNameInfo(), TemplateArgs,
16314 ME->getType(), ME->getValueKind(), ME->getObjectKind(), NOUR);
16315 return ExprEmpty();
16316 }
16317
16318 // FIXME: Implement this.
16319 // -- If e is a pointer-to-member expression of the form e1 .* e2 ...
16320
16321 // -- If e has the form (e1)...
16322 case Expr::ParenExprClass: {
16323 auto *PE = dyn_cast<ParenExpr>(E);
16324 ExprResult Sub = Rebuild(PE->getSubExpr());
16325 if (!Sub.isUsable())
16326 return Sub;
16327 return S.ActOnParenExpr(PE->getLParen(), PE->getRParen(), Sub.get());
16328 }
16329
16330 // FIXME: Implement these.
16331 // -- If e is a glvalue conditional expression, ...
16332 // -- If e is a comma expression, ...
16333
16334 // [Clang extension]
16335 // -- If e has the form __extension__ e1...
16336 case Expr::UnaryOperatorClass: {
16337 auto *UO = cast<UnaryOperator>(E);
16338 if (UO->getOpcode() != UO_Extension)
16339 break;
16340 ExprResult Sub = Rebuild(UO->getSubExpr());
16341 if (!Sub.isUsable())
16342 return Sub;
16343 return S.BuildUnaryOp(nullptr, UO->getOperatorLoc(), UO_Extension,
16344 Sub.get());
16345 }
16346
16347 // [Clang extension]
16348 // -- If e has the form _Generic(...), the set of potential results is the
16349 // union of the sets of potential results of the associated expressions.
16350 case Expr::GenericSelectionExprClass: {
16351 auto *GSE = dyn_cast<GenericSelectionExpr>(E);
16352
16353 SmallVector<Expr *, 4> AssocExprs;
16354 bool AnyChanged = false;
16355 for (Expr *OrigAssocExpr : GSE->getAssocExprs()) {
16356 ExprResult AssocExpr = Rebuild(OrigAssocExpr);
16357 if (AssocExpr.isInvalid())
16358 return ExprError();
16359 if (AssocExpr.isUsable()) {
16360 AssocExprs.push_back(AssocExpr.get());
16361 AnyChanged = true;
16362 } else {
16363 AssocExprs.push_back(OrigAssocExpr);
16364 }
16365 }
16366
16367 return AnyChanged ? S.CreateGenericSelectionExpr(
16368 GSE->getGenericLoc(), GSE->getDefaultLoc(),
16369 GSE->getRParenLoc(), GSE->getControllingExpr(),
16370 GSE->getAssocTypeSourceInfos(), AssocExprs)
16371 : ExprEmpty();
16372 }
16373
16374 // [Clang extension]
16375 // -- If e has the form __builtin_choose_expr(...), the set of potential
16376 // results is the union of the sets of potential results of the
16377 // second and third subexpressions.
16378 case Expr::ChooseExprClass: {
16379 auto *CE = dyn_cast<ChooseExpr>(E);
16380
16381 ExprResult LHS = Rebuild(CE->getLHS());
16382 if (LHS.isInvalid())
16383 return ExprError();
16384
16385 ExprResult RHS = Rebuild(CE->getLHS());
16386 if (RHS.isInvalid())
16387 return ExprError();
16388
16389 if (!LHS.get() && !RHS.get())
16390 return ExprEmpty();
16391 if (!LHS.isUsable())
16392 LHS = CE->getLHS();
16393 if (!RHS.isUsable())
16394 RHS = CE->getRHS();
16395
16396 return S.ActOnChooseExpr(CE->getBuiltinLoc(), CE->getCond(), LHS.get(),
16397 RHS.get(), CE->getRParenLoc());
16398 }
16399
16400 // Step through non-syntactic nodes.
16401 case Expr::ConstantExprClass: {
16402 auto *CE = dyn_cast<ConstantExpr>(E);
16403 ExprResult Sub = Rebuild(CE->getSubExpr());
16404 if (!Sub.isUsable())
16405 return Sub;
16406 return ConstantExpr::Create(S.Context, Sub.get());
16407 }
16408
16409 default:
16410 break;
16411 }
16412
16413 // Can't traverse through this node. Nothing to do.
16414 return ExprEmpty();
16415}
16416
16417ExprResult Sema::CheckLValueToRValueConversionOperand(Expr *E) {
16418 // C++2a [basic.def.odr]p4:
16419 // [...] an expression of non-volatile-qualified non-class type to which
16420 // the lvalue-to-rvalue conversion is applied [...]
16421 if (E->getType().isVolatileQualified() || E->getType()->getAs<RecordType>())
16422 return E;
16423
16424 ExprResult Result =
16425 rebuildPotentialResultsAsNonOdrUsed(*this, E, NOUR_Constant);
16426 if (Result.isInvalid())
16427 return ExprError();
16428 return Result.get() ? Result : E;
16429}
16430
16431ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
16432 Res = CorrectDelayedTyposInExpr(Res);
16433
16434 if (!Res.isUsable())
16435 return Res;
16436
16437 // If a constant-expression is a reference to a variable where we delay
16438 // deciding whether it is an odr-use, just assume we will apply the
16439 // lvalue-to-rvalue conversion. In the one case where this doesn't happen
16440 // (a non-type template argument), we have special handling anyway.
16441 return CheckLValueToRValueConversionOperand(Res.get());
16442}
16443
16444void Sema::CleanupVarDeclMarking() {
16445 // Iterate through a local copy in case MarkVarDeclODRUsed makes a recursive
16446 // call.
16447 MaybeODRUseExprSet LocalMaybeODRUseExprs;
16448 std::swap(LocalMaybeODRUseExprs, MaybeODRUseExprs);
16449
16450 for (Expr *E : LocalMaybeODRUseExprs) {
16451 if (auto *DRE = dyn_cast<DeclRefExpr>(E)) {
16452 MarkVarDeclODRUsed(cast<VarDecl>(DRE->getDecl()),
16453 DRE->getLocation(), *this);
16454 } else if (auto *ME = dyn_cast<MemberExpr>(E)) {
16455 MarkVarDeclODRUsed(cast<VarDecl>(ME->getMemberDecl()), ME->getMemberLoc(),
16456 *this);
16457 } else if (auto *FP = dyn_cast<FunctionParmPackExpr>(E)) {
16458 for (VarDecl *VD : *FP)
16459 MarkVarDeclODRUsed(VD, FP->getParameterPackLocation(), *this);
16460 } else {
16461 llvm_unreachable("Unexpected expression");
16462 }
16463 }
16464
16465 assert(MaybeODRUseExprs.empty() &&
16466 "MarkVarDeclODRUsed failed to cleanup MaybeODRUseExprs?");
16467}
16468
16469static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc,
16470 VarDecl *Var, Expr *E) {
16471 assert((!E || isa<DeclRefExpr>(E) || isa<MemberExpr>(E) ||
16472 isa<FunctionParmPackExpr>(E)) &&
16473 "Invalid Expr argument to DoMarkVarDeclReferenced");
16474 Var->setReferenced();
16475
16476 if (Var->isInvalidDecl())
16477 return;
16478
16479 auto *MSI = Var->getMemberSpecializationInfo();
16480 TemplateSpecializationKind TSK = MSI ? MSI->getTemplateSpecializationKind()
16481 : Var->getTemplateSpecializationKind();
16482
16483 OdrUseContext OdrUse = isOdrUseContext(SemaRef);
16484 bool UsableInConstantExpr =
16485 Var->mightBeUsableInConstantExpressions(SemaRef.Context);
16486
16487 // C++20 [expr.const]p12:
16488 // A variable [...] is needed for constant evaluation if it is [...] a
16489 // variable whose name appears as a potentially constant evaluated
16490 // expression that is either a contexpr variable or is of non-volatile
16491 // const-qualified integral type or of reference type
16492 bool NeededForConstantEvaluation =
16493 isPotentiallyConstantEvaluatedContext(SemaRef) && UsableInConstantExpr;
16494
16495 bool NeedDefinition =
16496 OdrUse == OdrUseContext::Used || NeededForConstantEvaluation;
16497
16498 VarTemplateSpecializationDecl *VarSpec =
16499 dyn_cast<VarTemplateSpecializationDecl>(Var);
16500 assert(!isa<VarTemplatePartialSpecializationDecl>(Var) &&
16501 "Can't instantiate a partial template specialization.");
16502
16503 // If this might be a member specialization of a static data member, check
16504 // the specialization is visible. We already did the checks for variable
16505 // template specializations when we created them.
16506 if (NeedDefinition && TSK != TSK_Undeclared &&
16507 !isa<VarTemplateSpecializationDecl>(Var))
16508 SemaRef.checkSpecializationVisibility(Loc, Var);
16509
16510 // Perform implicit instantiation of static data members, static data member
16511 // templates of class templates, and variable template specializations. Delay
16512 // instantiations of variable templates, except for those that could be used
16513 // in a constant expression.
16514 if (NeedDefinition && isTemplateInstantiation(TSK)) {
16515 // Per C++17 [temp.explicit]p10, we may instantiate despite an explicit
16516 // instantiation declaration if a variable is usable in a constant
16517 // expression (among other cases).
16518 bool TryInstantiating =
16519 TSK == TSK_ImplicitInstantiation ||
16520 (TSK == TSK_ExplicitInstantiationDeclaration && UsableInConstantExpr);
16521
16522 if (TryInstantiating) {
16523 SourceLocation PointOfInstantiation =
16524 MSI ? MSI->getPointOfInstantiation() : Var->getPointOfInstantiation();
16525 bool FirstInstantiation = PointOfInstantiation.isInvalid();
16526 if (FirstInstantiation) {
16527 PointOfInstantiation = Loc;
16528 if (MSI)
16529 MSI->setPointOfInstantiation(PointOfInstantiation);
16530 else
16531 Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
16532 }
16533
16534 bool InstantiationDependent = false;
16535 bool IsNonDependent =
16536 VarSpec ? !TemplateSpecializationType::anyDependentTemplateArguments(
16537 VarSpec->getTemplateArgsInfo(), InstantiationDependent)
16538 : true;
16539
16540 // Do not instantiate specializations that are still type-dependent.
16541 if (IsNonDependent) {
16542 if (UsableInConstantExpr) {
16543 // Do not defer instantiations of variables that could be used in a
16544 // constant expression.
16545 SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var);
16546 } else if (FirstInstantiation ||
16547 isa<VarTemplateSpecializationDecl>(Var)) {
16548 // FIXME: For a specialization of a variable template, we don't
16549 // distinguish between "declaration and type implicitly instantiated"
16550 // and "implicit instantiation of definition requested", so we have
16551 // no direct way to avoid enqueueing the pending instantiation
16552 // multiple times.
16553 SemaRef.PendingInstantiations
16554 .push_back(std::make_pair(Var, PointOfInstantiation));
16555 }
16556 }
16557 }
16558 }
16559
16560 // C++2a [basic.def.odr]p4:
16561 // A variable x whose name appears as a potentially-evaluated expression e
16562 // is odr-used by e unless
16563 // -- x is a reference that is usable in constant expressions
16564 // -- x is a variable of non-reference type that is usable in constant
16565 // expressions and has no mutable subobjects [FIXME], and e is an
16566 // element of the set of potential results of an expression of
16567 // non-volatile-qualified non-class type to which the lvalue-to-rvalue
16568 // conversion is applied
16569 // -- x is a variable of non-reference type, and e is an element of the set
16570 // of potential results of a discarded-value expression to which the
16571 // lvalue-to-rvalue conversion is not applied [FIXME]
16572 //
16573 // We check the first part of the second bullet here, and
16574 // Sema::CheckLValueToRValueConversionOperand deals with the second part.
16575 // FIXME: To get the third bullet right, we need to delay this even for
16576 // variables that are not usable in constant expressions.
16577
16578 // If we already know this isn't an odr-use, there's nothing more to do.
16579 if (DeclRefExpr *DRE = dyn_cast_or_null<DeclRefExpr>(E))
16580 if (DRE->isNonOdrUse())
16581 return;
16582 if (MemberExpr *ME = dyn_cast_or_null<MemberExpr>(E))
16583 if (ME->isNonOdrUse())
16584 return;
16585
16586 switch (OdrUse) {
16587 case OdrUseContext::None:
16588 assert((!E || isa<FunctionParmPackExpr>(E)) &&
16589 "missing non-odr-use marking for unevaluated decl ref");
16590 break;
16591
16592 case OdrUseContext::FormallyOdrUsed:
16593 // FIXME: Ignoring formal odr-uses results in incorrect lambda capture
16594 // behavior.
16595 break;
16596
16597 case OdrUseContext::Used:
16598 // If we might later find that this expression isn't actually an odr-use,
16599 // delay the marking.
16600 if (E && Var->isUsableInConstantExpressions(SemaRef.Context))
16601 SemaRef.MaybeODRUseExprs.insert(E);
16602 else
16603 MarkVarDeclODRUsed(Var, Loc, SemaRef);
16604 break;
16605
16606 case OdrUseContext::Dependent:
16607 // If this is a dependent context, we don't need to mark variables as
16608 // odr-used, but we may still need to track them for lambda capture.
16609 // FIXME: Do we also need to do this inside dependent typeid expressions
16610 // (which are modeled as unevaluated at this point)?
16611 const bool RefersToEnclosingScope =
16612 (SemaRef.CurContext != Var->getDeclContext() &&
16613 Var->getDeclContext()->isFunctionOrMethod() && Var->hasLocalStorage());
16614 if (RefersToEnclosingScope) {
16615 LambdaScopeInfo *const LSI =
16616 SemaRef.getCurLambda(/*IgnoreNonLambdaCapturingScope=*/true);
16617 if (LSI && (!LSI->CallOperator ||
16618 !LSI->CallOperator->Encloses(Var->getDeclContext()))) {
16619 // If a variable could potentially be odr-used, defer marking it so
16620 // until we finish analyzing the full expression for any
16621 // lvalue-to-rvalue
16622 // or discarded value conversions that would obviate odr-use.
16623 // Add it to the list of potential captures that will be analyzed
16624 // later (ActOnFinishFullExpr) for eventual capture and odr-use marking
16625 // unless the variable is a reference that was initialized by a constant
16626 // expression (this will never need to be captured or odr-used).
16627 //
16628 // FIXME: We can simplify this a lot after implementing P0588R1.
16629 assert(E && "Capture variable should be used in an expression.");
16630 if (!Var->getType()->isReferenceType() ||
16631 !Var->isUsableInConstantExpressions(SemaRef.Context))
16632 LSI->addPotentialCapture(E->IgnoreParens());
16633 }
16634 }
16635 break;
16636 }
16637}
16638
16639/// Mark a variable referenced, and check whether it is odr-used
16640/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be
16641/// used directly for normal expressions referring to VarDecl.
16642void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) {
16643 DoMarkVarDeclReferenced(*this, Loc, Var, nullptr);
16644}
16645
16646static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc,
16647 Decl *D, Expr *E, bool MightBeOdrUse) {
16648 if (SemaRef.isInOpenMPDeclareTargetContext())
16649 SemaRef.checkDeclIsAllowedInOpenMPTarget(E, D);
16650
16651 if (VarDecl *Var = dyn_cast<VarDecl>(D)) {
16652 DoMarkVarDeclReferenced(SemaRef, Loc, Var, E);
16653 return;
16654 }
16655
16656 SemaRef.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse);
16657
16658 // If this is a call to a method via a cast, also mark the method in the
16659 // derived class used in case codegen can devirtualize the call.
16660 const MemberExpr *ME = dyn_cast<MemberExpr>(E);
16661 if (!ME)
16662 return;
16663 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ME->getMemberDecl());
16664 if (!MD)
16665 return;
16666 // Only attempt to devirtualize if this is truly a virtual call.
16667 bool IsVirtualCall = MD->isVirtual() &&
16668 ME->performsVirtualDispatch(SemaRef.getLangOpts());
16669 if (!IsVirtualCall)
16670 return;
16671
16672 // If it's possible to devirtualize the call, mark the called function
16673 // referenced.
16674 CXXMethodDecl *DM = MD->getDevirtualizedMethod(
16675 ME->getBase(), SemaRef.getLangOpts().AppleKext);
16676 if (DM)
16677 SemaRef.MarkAnyDeclReferenced(Loc, DM, MightBeOdrUse);
16678}
16679
16680/// Perform reference-marking and odr-use handling for a DeclRefExpr.
16681void Sema::MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base) {
16682 // TODO: update this with DR# once a defect report is filed.
16683 // C++11 defect. The address of a pure member should not be an ODR use, even
16684 // if it's a qualified reference.
16685 bool OdrUse = true;
16686 if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getDecl()))
16687 if (Method->isVirtual() &&
16688 !Method->getDevirtualizedMethod(Base, getLangOpts().AppleKext))
16689 OdrUse = false;
16690 MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse);
16691}
16692
16693/// Perform reference-marking and odr-use handling for a MemberExpr.
16694void Sema::MarkMemberReferenced(MemberExpr *E) {
16695 // C++11 [basic.def.odr]p2:
16696 // A non-overloaded function whose name appears as a potentially-evaluated
16697 // expression or a member of a set of candidate functions, if selected by
16698 // overload resolution when referred to from a potentially-evaluated
16699 // expression, is odr-used, unless it is a pure virtual function and its
16700 // name is not explicitly qualified.
16701 bool MightBeOdrUse = true;
16702 if (E->performsVirtualDispatch(getLangOpts())) {
16703 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getMemberDecl()))
16704 if (Method->isPure())
16705 MightBeOdrUse = false;
16706 }
16707 SourceLocation Loc =
16708 E->getMemberLoc().isValid() ? E->getMemberLoc() : E->getBeginLoc();
16709 MarkExprReferenced(*this, Loc, E->getMemberDecl(), E, MightBeOdrUse);
16710}
16711
16712/// Perform reference-marking and odr-use handling for a FunctionParmPackExpr.
16713void Sema::MarkFunctionParmPackReferenced(FunctionParmPackExpr *E) {
16714 for (VarDecl *VD : *E)
16715 MarkExprReferenced(*this, E->getParameterPackLocation(), VD, E, true);
16716}
16717
16718/// Perform marking for a reference to an arbitrary declaration. It
16719/// marks the declaration referenced, and performs odr-use checking for
16720/// functions and variables. This method should not be used when building a
16721/// normal expression which refers to a variable.
16722void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D,
16723 bool MightBeOdrUse) {
16724 if (MightBeOdrUse) {
16725 if (auto *VD = dyn_cast<VarDecl>(D)) {
16726 MarkVariableReferenced(Loc, VD);
16727 return;
16728 }
16729 }
16730 if (auto *FD = dyn_cast<FunctionDecl>(D)) {
16731 MarkFunctionReferenced(Loc, FD, MightBeOdrUse);
16732 return;
16733 }
16734 D->setReferenced();
16735}
16736
16737namespace {
16738 // Mark all of the declarations used by a type as referenced.
16739 // FIXME: Not fully implemented yet! We need to have a better understanding
16740 // of when we're entering a context we should not recurse into.
16741 // FIXME: This is and EvaluatedExprMarker are more-or-less equivalent to
16742 // TreeTransforms rebuilding the type in a new context. Rather than
16743 // duplicating the TreeTransform logic, we should consider reusing it here.
16744 // Currently that causes problems when rebuilding LambdaExprs.
16745 class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> {
16746 Sema &S;
16747 SourceLocation Loc;
16748
16749 public:
16750 typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited;
16751
16752 MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { }
16753
16754 bool TraverseTemplateArgument(const TemplateArgument &Arg);
16755 };
16756}
16757
16758bool MarkReferencedDecls::TraverseTemplateArgument(
16759 const TemplateArgument &Arg) {
16760 {
16761 // A non-type template argument is a constant-evaluated context.
16762 EnterExpressionEvaluationContext Evaluated(
16763 S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
16764 if (Arg.getKind() == TemplateArgument::Declaration) {
16765 if (Decl *D = Arg.getAsDecl())
16766 S.MarkAnyDeclReferenced(Loc, D, true);
16767 } else if (Arg.getKind() == TemplateArgument::Expression) {
16768 S.MarkDeclarationsReferencedInExpr(Arg.getAsExpr(), false);
16769 }
16770 }
16771
16772 return Inherited::TraverseTemplateArgument(Arg);
16773}
16774
16775void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) {
16776 MarkReferencedDecls Marker(*this, Loc);
16777 Marker.TraverseType(T);
16778}
16779
16780namespace {
16781 /// Helper class that marks all of the declarations referenced by
16782 /// potentially-evaluated subexpressions as "referenced".
16783 class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> {
16784 Sema &S;
16785 bool SkipLocalVariables;
16786
16787 public:
16788 typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited;
16789
16790 EvaluatedExprMarker(Sema &S, bool SkipLocalVariables)
16791 : Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { }
16792
16793 void VisitDeclRefExpr(DeclRefExpr *E) {
16794 // If we were asked not to visit local variables, don't.
16795 if (SkipLocalVariables) {
16796 if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
16797 if (VD->hasLocalStorage())
16798 return;
16799 }
16800
16801 S.MarkDeclRefReferenced(E);
16802 }
16803
16804 void VisitMemberExpr(MemberExpr *E) {
16805 S.MarkMemberReferenced(E);
16806 Inherited::VisitMemberExpr(E);
16807 }
16808
16809 void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
16810 S.MarkFunctionReferenced(
16811 E->getBeginLoc(),
16812 const_cast<CXXDestructorDecl *>(E->getTemporary()->getDestructor()));
16813 Visit(E->getSubExpr());
16814 }
16815
16816 void VisitCXXNewExpr(CXXNewExpr *E) {
16817 if (E->getOperatorNew())
16818 S.MarkFunctionReferenced(E->getBeginLoc(), E->getOperatorNew());
16819 if (E->getOperatorDelete())
16820 S.MarkFunctionReferenced(E->getBeginLoc(), E->getOperatorDelete());
16821 Inherited::VisitCXXNewExpr(E);
16822 }
16823
16824 void VisitCXXDeleteExpr(CXXDeleteExpr *E) {
16825 if (E->getOperatorDelete())
16826 S.MarkFunctionReferenced(E->getBeginLoc(), E->getOperatorDelete());
16827 QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType());
16828 if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) {
16829 CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl());
16830 S.MarkFunctionReferenced(E->getBeginLoc(), S.LookupDestructor(Record));
16831 }
16832
16833 Inherited::VisitCXXDeleteExpr(E);
16834 }
16835
16836 void VisitCXXConstructExpr(CXXConstructExpr *E) {
16837 S.MarkFunctionReferenced(E->getBeginLoc(), E->getConstructor());
16838 Inherited::VisitCXXConstructExpr(E);
16839 }
16840
16841 void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
16842 Visit(E->getExpr());
16843 }
16844 };
16845}
16846
16847/// Mark any declarations that appear within this expression or any
16848/// potentially-evaluated subexpressions as "referenced".
16849///
16850/// \param SkipLocalVariables If true, don't mark local variables as
16851/// 'referenced'.
16852void Sema::MarkDeclarationsReferencedInExpr(Expr *E,
16853 bool SkipLocalVariables) {
16854 EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E);
16855}
16856
16857/// Emit a diagnostic that describes an effect on the run-time behavior
16858/// of the program being compiled.
16859///
16860/// This routine emits the given diagnostic when the code currently being
16861/// type-checked is "potentially evaluated", meaning that there is a
16862/// possibility that the code will actually be executable. Code in sizeof()
16863/// expressions, code used only during overload resolution, etc., are not
16864/// potentially evaluated. This routine will suppress such diagnostics or,
16865/// in the absolutely nutty case of potentially potentially evaluated
16866/// expressions (C++ typeid), queue the diagnostic to potentially emit it
16867/// later.
16868///
16869/// This routine should be used for all diagnostics that describe the run-time
16870/// behavior of a program, such as passing a non-POD value through an ellipsis.
16871/// Failure to do so will likely result in spurious diagnostics or failures
16872/// during overload resolution or within sizeof/alignof/typeof/typeid.
16873bool Sema::DiagRuntimeBehavior(SourceLocation Loc, ArrayRef<const Stmt*> Stmts,
16874 const PartialDiagnostic &PD) {
16875 switch (ExprEvalContexts.back().Context) {
16876 case ExpressionEvaluationContext::Unevaluated:
16877 case ExpressionEvaluationContext::UnevaluatedList:
16878 case ExpressionEvaluationContext::UnevaluatedAbstract:
16879 case ExpressionEvaluationContext::DiscardedStatement:
16880 // The argument will never be evaluated, so don't complain.
16881 break;
16882
16883 case ExpressionEvaluationContext::ConstantEvaluated:
16884 // Relevant diagnostics should be produced by constant evaluation.
16885 break;
16886
16887 case ExpressionEvaluationContext::PotentiallyEvaluated:
16888 case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
16889 if (!Stmts.empty() && getCurFunctionOrMethodDecl()) {
16890 FunctionScopes.back()->PossiblyUnreachableDiags.
16891 push_back(sema::PossiblyUnreachableDiag(PD, Loc, Stmts));
16892 return true;
16893 }
16894
16895 // The initializer of a constexpr variable or of the first declaration of a
16896 // static data member is not syntactically a constant evaluated constant,
16897 // but nonetheless is always required to be a constant expression, so we
16898 // can skip diagnosing.
16899 // FIXME: Using the mangling context here is a hack.
16900 if (auto *VD = dyn_cast_or_null<VarDecl>(
16901 ExprEvalContexts.back().ManglingContextDecl)) {
16902 if (VD->isConstexpr() ||
16903 (VD->isStaticDataMember() && VD->isFirstDecl() && !VD->isInline()))
16904 break;
16905 // FIXME: For any other kind of variable, we should build a CFG for its
16906 // initializer and check whether the context in question is reachable.
16907 }
16908
16909 Diag(Loc, PD);
16910 return true;
16911 }
16912
16913 return false;
16914}
16915
16916bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
16917 const PartialDiagnostic &PD) {
16918 return DiagRuntimeBehavior(
16919 Loc, Statement ? llvm::makeArrayRef(Statement) : llvm::None, PD);
16920}
16921
16922bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
16923 CallExpr *CE, FunctionDecl *FD) {
16924 if (ReturnType->isVoidType() || !ReturnType->isIncompleteType())
16925 return false;
16926
16927 // If we're inside a decltype's expression, don't check for a valid return
16928 // type or construct temporaries until we know whether this is the last call.
16929 if (ExprEvalContexts.back().ExprContext ==
16930 ExpressionEvaluationContextRecord::EK_Decltype) {
16931 ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE);
16932 return false;
16933 }
16934
16935 class CallReturnIncompleteDiagnoser : public TypeDiagnoser {
16936 FunctionDecl *FD;
16937 CallExpr *CE;
16938
16939 public:
16940 CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE)
16941 : FD(FD), CE(CE) { }
16942
16943 void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
16944 if (!FD) {
16945 S.Diag(Loc, diag::err_call_incomplete_return)
16946 << T << CE->getSourceRange();
16947 return;
16948 }
16949
16950 S.Diag(Loc, diag::err_call_function_incomplete_return)
16951 << CE->getSourceRange() << FD->getDeclName() << T;
16952 S.Diag(FD->getLocation(), diag::note_entity_declared_at)
16953 << FD->getDeclName();
16954 }
16955 } Diagnoser(FD, CE);
16956
16957 if (RequireCompleteType(Loc, ReturnType, Diagnoser))
16958 return true;
16959
16960 return false;
16961}
16962
16963// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses
16964// will prevent this condition from triggering, which is what we want.
16965void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
16966 SourceLocation Loc;
16967
16968 unsigned diagnostic = diag::warn_condition_is_assignment;
16969 bool IsOrAssign = false;
16970
16971 if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
16972 if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign)
16973 return;
16974
16975 IsOrAssign = Op->getOpcode() == BO_OrAssign;
16976
16977 // Greylist some idioms by putting them into a warning subcategory.
16978 if (ObjCMessageExpr *ME
16979 = dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) {
16980 Selector Sel = ME->getSelector();
16981
16982 // self = [<foo> init...]
16983 if (isSelfExpr(Op->getLHS()) && ME->getMethodFamily() == OMF_init)
16984 diagnostic = diag::warn_condition_is_idiomatic_assignment;
16985
16986 // <foo> = [<bar> nextObject]
16987 else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject")
16988 diagnostic = diag::warn_condition_is_idiomatic_assignment;
16989 }
16990
16991 Loc = Op->getOperatorLoc();
16992 } else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
16993 if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual)
16994 return;
16995
16996 IsOrAssign = Op->getOperator() == OO_PipeEqual;
16997 Loc = Op->getOperatorLoc();
16998 } else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E))
16999 return DiagnoseAssignmentAsCondition(POE->getSyntacticForm());
17000 else {
17001 // Not an assignment.
17002 return;
17003 }
17004
17005 Diag(Loc, diagnostic) << E->getSourceRange();
17006
17007 SourceLocation Open = E->getBeginLoc();
17008 SourceLocation Close = getLocForEndOfToken(E->getSourceRange().getEnd());
17009 Diag(Loc, diag::note_condition_assign_silence)
17010 << FixItHint::CreateInsertion(Open, "(")
17011 << FixItHint::CreateInsertion(Close, ")");
17012
17013 if (IsOrAssign)
17014 Diag(Loc, diag::note_condition_or_assign_to_comparison)
17015 << FixItHint::CreateReplacement(Loc, "!=");
17016 else
17017 Diag(Loc, diag::note_condition_assign_to_comparison)
17018 << FixItHint::CreateReplacement(Loc, "==");
17019}
17020
17021/// Redundant parentheses over an equality comparison can indicate
17022/// that the user intended an assignment used as condition.
17023void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) {
17024 // Don't warn if the parens came from a macro.
17025 SourceLocation parenLoc = ParenE->getBeginLoc();
17026 if (parenLoc.isInvalid() || parenLoc.isMacroID())
17027 return;
17028 // Don't warn for dependent expressions.
17029 if (ParenE->isTypeDependent())
17030 return;
17031
17032 Expr *E = ParenE->IgnoreParens();
17033
17034 if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E))
17035 if (opE->getOpcode() == BO_EQ &&
17036 opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context)
17037 == Expr::MLV_Valid) {
17038 SourceLocation Loc = opE->getOperatorLoc();
17039
17040 Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange();
17041 SourceRange ParenERange = ParenE->getSourceRange();
17042 Diag(Loc, diag::note_equality_comparison_silence)
17043 << FixItHint::CreateRemoval(ParenERange.getBegin())
17044 << FixItHint::CreateRemoval(ParenERange.getEnd());
17045 Diag(Loc, diag::note_equality_comparison_to_assign)
17046 << FixItHint::CreateReplacement(Loc, "=");
17047 }
17048}
17049
17050ExprResult Sema::CheckBooleanCondition(SourceLocation Loc, Expr *E,
17051 bool IsConstexpr) {
17052 DiagnoseAssignmentAsCondition(E);
17053 if (ParenExpr *parenE = dyn_cast<ParenExpr>(E))
17054 DiagnoseEqualityWithExtraParens(parenE);
17055
17056 ExprResult result = CheckPlaceholderExpr(E);
17057 if (result.isInvalid()) return ExprError();
17058 E = result.get();
17059
17060 if (!E->isTypeDependent()) {
17061 if (getLangOpts().CPlusPlus)
17062 return CheckCXXBooleanCondition(E, IsConstexpr); // C++ 6.4p4
17063
17064 ExprResult ERes = DefaultFunctionArrayLvalueConversion(E);
17065 if (ERes.isInvalid())
17066 return ExprError();
17067 E = ERes.get();
17068
17069 QualType T = E->getType();
17070 if (!T->isScalarType()) { // C99 6.8.4.1p1
17071 Diag(Loc, diag::err_typecheck_statement_requires_scalar)
17072 << T << E->getSourceRange();
17073 return ExprError();
17074 }
17075 CheckBoolLikeConversion(E, Loc);
17076 }
17077
17078 return E;
17079}
17080
17081Sema::ConditionResult Sema::ActOnCondition(Scope *S, SourceLocation Loc,
17082 Expr *SubExpr, ConditionKind CK) {
17083 // Empty conditions are valid in for-statements.
17084 if (!SubExpr)
17085 return ConditionResult();
17086
17087 ExprResult Cond;
17088 switch (CK) {
17089 case ConditionKind::Boolean:
17090 Cond = CheckBooleanCondition(Loc, SubExpr);
17091 break;
17092
17093 case ConditionKind::ConstexprIf:
17094 Cond = CheckBooleanCondition(Loc, SubExpr, true);
17095 break;
17096
17097 case ConditionKind::Switch:
17098 Cond = CheckSwitchCondition(Loc, SubExpr);
17099 break;
17100 }
17101 if (Cond.isInvalid())
17102 return ConditionError();
17103
17104 // FIXME: FullExprArg doesn't have an invalid bit, so check nullness instead.
17105 FullExprArg FullExpr = MakeFullExpr(Cond.get(), Loc);
17106 if (!FullExpr.get())
17107 return ConditionError();
17108
17109 return ConditionResult(*this, nullptr, FullExpr,
17110 CK == ConditionKind::ConstexprIf);
17111}
17112
17113namespace {
17114 /// A visitor for rebuilding a call to an __unknown_any expression
17115 /// to have an appropriate type.
17116 struct RebuildUnknownAnyFunction
17117 : StmtVisitor<RebuildUnknownAnyFunction, ExprResult> {
17118
17119 Sema &S;
17120
17121 RebuildUnknownAnyFunction(Sema &S) : S(S) {}
17122
17123 ExprResult VisitStmt(Stmt *S) {
17124 llvm_unreachable("unexpected statement!");
17125 }
17126
17127 ExprResult VisitExpr(Expr *E) {
17128 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call)
17129 << E->getSourceRange();
17130 return ExprError();
17131 }
17132
17133 /// Rebuild an expression which simply semantically wraps another
17134 /// expression which it shares the type and value kind of.
17135 template <class T> ExprResult rebuildSugarExpr(T *E) {
17136 ExprResult SubResult = Visit(E->getSubExpr());
17137 if (SubResult.isInvalid()) return ExprError();
17138
17139 Expr *SubExpr = SubResult.get();
17140 E->setSubExpr(SubExpr);
17141 E->setType(SubExpr->getType());
17142 E->setValueKind(SubExpr->getValueKind());
17143 assert(E->getObjectKind() == OK_Ordinary);
17144 return E;
17145 }
17146
17147 ExprResult VisitParenExpr(ParenExpr *E) {
17148 return rebuildSugarExpr(E);
17149 }
17150
17151 ExprResult VisitUnaryExtension(UnaryOperator *E) {
17152 return rebuildSugarExpr(E);
17153 }
17154
17155 ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
17156 ExprResult SubResult = Visit(E->getSubExpr());
17157 if (SubResult.isInvalid()) return ExprError();
17158
17159 Expr *SubExpr = SubResult.get();
17160 E->setSubExpr(SubExpr);
17161 E->setType(S.Context.getPointerType(SubExpr->getType()));
17162 assert(E->getValueKind() == VK_RValue);
17163 assert(E->getObjectKind() == OK_Ordinary);
17164 return E;
17165 }
17166
17167 ExprResult resolveDecl(Expr *E, ValueDecl *VD) {
17168 if (!isa<FunctionDecl>(VD)) return VisitExpr(E);
17169
17170 E->setType(VD->getType());
17171
17172 assert(E->getValueKind() == VK_RValue);
17173 if (S.getLangOpts().CPlusPlus &&
17174 !(isa<CXXMethodDecl>(VD) &&
17175 cast<CXXMethodDecl>(VD)->isInstance()))
17176 E->setValueKind(VK_LValue);
17177
17178 return E;
17179 }
17180
17181 ExprResult VisitMemberExpr(MemberExpr *E) {
17182 return resolveDecl(E, E->getMemberDecl());
17183 }
17184
17185 ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
17186 return resolveDecl(E, E->getDecl());
17187 }
17188 };
17189}
17190
17191/// Given a function expression of unknown-any type, try to rebuild it
17192/// to have a function type.
17193static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) {
17194 ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr);
17195 if (Result.isInvalid()) return ExprError();
17196 return S.DefaultFunctionArrayConversion(Result.get());
17197}
17198
17199namespace {
17200 /// A visitor for rebuilding an expression of type __unknown_anytype
17201 /// into one which resolves the type directly on the referring
17202 /// expression. Strict preservation of the original source
17203 /// structure is not a goal.
17204 struct RebuildUnknownAnyExpr
17205 : StmtVisitor<RebuildUnknownAnyExpr, ExprResult> {
17206
17207 Sema &S;
17208
17209 /// The current destination type.
17210 QualType DestType;
17211
17212 RebuildUnknownAnyExpr(Sema &S, QualType CastType)
17213 : S(S), DestType(CastType) {}
17214
17215 ExprResult VisitStmt(Stmt *S) {
17216 llvm_unreachable("unexpected statement!");
17217 }
17218
17219 ExprResult VisitExpr(Expr *E) {
17220 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
17221 << E->getSourceRange();
17222 return ExprError();
17223 }
17224
17225 ExprResult VisitCallExpr(CallExpr *E);
17226 ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E);
17227
17228 /// Rebuild an expression which simply semantically wraps another
17229 /// expression which it shares the type and value kind of.
17230 template <class T> ExprResult rebuildSugarExpr(T *E) {
17231 ExprResult SubResult = Visit(E->getSubExpr());
17232 if (SubResult.isInvalid()) return ExprError();
17233 Expr *SubExpr = SubResult.get();
17234 E->setSubExpr(SubExpr);
17235 E->setType(SubExpr->getType());
17236 E->setValueKind(SubExpr->getValueKind());
17237 assert(E->getObjectKind() == OK_Ordinary);
17238 return E;
17239 }
17240
17241 ExprResult VisitParenExpr(ParenExpr *E) {
17242 return rebuildSugarExpr(E);
17243 }
17244
17245 ExprResult VisitUnaryExtension(UnaryOperator *E) {
17246 return rebuildSugarExpr(E);
17247 }
17248
17249 ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
17250 const PointerType *Ptr = DestType->getAs<PointerType>();
17251 if (!Ptr) {
17252 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof)
17253 << E->getSourceRange();
17254 return ExprError();
17255 }
17256
17257 if (isa<CallExpr>(E->getSubExpr())) {
17258 S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof_call)
17259 << E->getSourceRange();
17260 return ExprError();
17261 }
17262
17263 assert(E->getValueKind() == VK_RValue);
17264 assert(E->getObjectKind() == OK_Ordinary);
17265 E->setType(DestType);
17266
17267 // Build the sub-expression as if it were an object of the pointee type.
17268 DestType = Ptr->getPointeeType();
17269 ExprResult SubResult = Visit(E->getSubExpr());
17270 if (SubResult.isInvalid()) return ExprError();
17271 E->setSubExpr(SubResult.get());
17272 return E;
17273 }
17274
17275 ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E);
17276
17277 ExprResult resolveDecl(Expr *E, ValueDecl *VD);
17278
17279 ExprResult VisitMemberExpr(MemberExpr *E) {
17280 return resolveDecl(E, E->getMemberDecl());
17281 }
17282
17283 ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
17284 return resolveDecl(E, E->getDecl());
17285 }
17286 };
17287}
17288
17289/// Rebuilds a call expression which yielded __unknown_anytype.
17290ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) {
17291 Expr *CalleeExpr = E->getCallee();
17292
17293 enum FnKind {
17294 FK_MemberFunction,
17295 FK_FunctionPointer,
17296 FK_BlockPointer
17297 };
17298
17299 FnKind Kind;
17300 QualType CalleeType = CalleeExpr->getType();
17301 if (CalleeType == S.Context.BoundMemberTy) {
17302 assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E));
17303 Kind = FK_MemberFunction;
17304 CalleeType = Expr::findBoundMemberType(CalleeExpr);
17305 } else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) {
17306 CalleeType = Ptr->getPointeeType();
17307 Kind = FK_FunctionPointer;
17308 } else {
17309 CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType();
17310 Kind = FK_BlockPointer;
17311 }
17312 const FunctionType *FnType = CalleeType->castAs<FunctionType>();
17313
17314 // Verify that this is a legal result type of a function.
17315 if (DestType->isArrayType() || DestType->isFunctionType()) {
17316 unsigned diagID = diag::err_func_returning_array_function;
17317 if (Kind == FK_BlockPointer)
17318 diagID = diag::err_block_returning_array_function;
17319
17320 S.Diag(E->getExprLoc(), diagID)
17321 << DestType->isFunctionType() << DestType;
17322 return ExprError();
17323 }
17324
17325 // Otherwise, go ahead and set DestType as the call's result.
17326 E->setType(DestType.getNonLValueExprType(S.Context));
17327 E->setValueKind(Expr::getValueKindForType(DestType));
17328 assert(E->getObjectKind() == OK_Ordinary);
17329
17330 // Rebuild the function type, replacing the result type with DestType.
17331 const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType);
17332 if (Proto) {
17333 // __unknown_anytype(...) is a special case used by the debugger when
17334 // it has no idea what a function's signature is.
17335 //
17336 // We want to build this call essentially under the K&R
17337 // unprototyped rules, but making a FunctionNoProtoType in C++
17338 // would foul up all sorts of assumptions. However, we cannot
17339 // simply pass all arguments as variadic arguments, nor can we
17340 // portably just call the function under a non-variadic type; see
17341 // the comment on IR-gen's TargetInfo::isNoProtoCallVariadic.
17342 // However, it turns out that in practice it is generally safe to
17343 // call a function declared as "A foo(B,C,D);" under the prototype
17344 // "A foo(B,C,D,...);". The only known exception is with the
17345 // Windows ABI, where any variadic function is implicitly cdecl
17346 // regardless of its normal CC. Therefore we change the parameter
17347 // types to match the types of the arguments.
17348 //
17349 // This is a hack, but it is far superior to moving the
17350 // corresponding target-specific code from IR-gen to Sema/AST.
17351
17352 ArrayRef<QualType> ParamTypes = Proto->getParamTypes();
17353 SmallVector<QualType, 8> ArgTypes;
17354 if (ParamTypes.empty() && Proto->isVariadic()) { // the special case
17355 ArgTypes.reserve(E->getNumArgs());
17356 for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
17357 Expr *Arg = E->getArg(i);
17358 QualType ArgType = Arg->getType();
17359 if (E->isLValue()) {
17360 ArgType = S.Context.getLValueReferenceType(ArgType);
17361 } else if (E->isXValue()) {
17362 ArgType = S.Context.getRValueReferenceType(ArgType);
17363 }
17364 ArgTypes.push_back(ArgType);
17365 }
17366 ParamTypes = ArgTypes;
17367 }
17368 DestType = S.Context.getFunctionType(DestType, ParamTypes,
17369 Proto->getExtProtoInfo());
17370 } else {
17371 DestType = S.Context.getFunctionNoProtoType(DestType,
17372 FnType->getExtInfo());
17373 }
17374
17375 // Rebuild the appropriate pointer-to-function type.
17376 switch (Kind) {
17377 case FK_MemberFunction:
17378 // Nothing to do.
17379 break;
17380
17381 case FK_FunctionPointer:
17382 DestType = S.Context.getPointerType(DestType);
17383 break;
17384
17385 case FK_BlockPointer:
17386 DestType = S.Context.getBlockPointerType(DestType);
17387 break;
17388 }
17389
17390 // Finally, we can recurse.
17391 ExprResult CalleeResult = Visit(CalleeExpr);
17392 if (!CalleeResult.isUsable()) return ExprError();
17393 E->setCallee(CalleeResult.get());
17394
17395 // Bind a temporary if necessary.
17396 return S.MaybeBindToTemporary(E);
17397}
17398
17399ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) {
17400 // Verify that this is a legal result type of a call.
17401 if (DestType->isArrayType() || DestType->isFunctionType()) {
17402 S.Diag(E->getExprLoc(), diag::err_func_returning_array_function)
17403 << DestType->isFunctionType() << DestType;
17404 return ExprError();
17405 }
17406
17407 // Rewrite the method result type if available.
17408 if (ObjCMethodDecl *Method = E->getMethodDecl()) {
17409 assert(Method->getReturnType() == S.Context.UnknownAnyTy);
17410 Method->setReturnType(DestType);
17411 }
17412
17413 // Change the type of the message.
17414 E->setType(DestType.getNonReferenceType());
17415 E->setValueKind(Expr::getValueKindForType(DestType));
17416
17417 return S.MaybeBindToTemporary(E);
17418}
17419
17420ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) {
17421 // The only case we should ever see here is a function-to-pointer decay.
17422 if (E->getCastKind() == CK_FunctionToPointerDecay) {
17423 assert(E->getValueKind() == VK_RValue);
17424 assert(E->getObjectKind() == OK_Ordinary);
17425
17426 E->setType(DestType);
17427
17428 // Rebuild the sub-expression as the pointee (function) type.
17429 DestType = DestType->castAs<PointerType>()->getPointeeType();
17430
17431 ExprResult Result = Visit(E->getSubExpr());
17432 if (!Result.isUsable()) return ExprError();
17433
17434 E->setSubExpr(Result.get());
17435 return E;
17436 } else if (E->getCastKind() == CK_LValueToRValue) {
17437 assert(E->getValueKind() == VK_RValue);
17438 assert(E->getObjectKind() == OK_Ordinary);
17439
17440 assert(isa<BlockPointerType>(E->getType()));
17441
17442 E->setType(DestType);
17443
17444 // The sub-expression has to be a lvalue reference, so rebuild it as such.
17445 DestType = S.Context.getLValueReferenceType(DestType);
17446
17447 ExprResult Result = Visit(E->getSubExpr());
17448 if (!Result.isUsable()) return ExprError();
17449
17450 E->setSubExpr(Result.get());
17451 return E;
17452 } else {
17453 llvm_unreachable("Unhandled cast type!");
17454 }
17455}
17456
17457ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) {
17458 ExprValueKind ValueKind = VK_LValue;
17459 QualType Type = DestType;
17460
17461 // We know how to make this work for certain kinds of decls:
17462
17463 // - functions
17464 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) {
17465 if (const PointerType *Ptr = Type->getAs<PointerType>()) {
17466 DestType = Ptr->getPointeeType();
17467 ExprResult Result = resolveDecl(E, VD);
17468 if (Result.isInvalid()) return ExprError();
17469 return S.ImpCastExprToType(Result.get(), Type,
17470 CK_FunctionToPointerDecay, VK_RValue);
17471 }
17472
17473 if (!Type->isFunctionType()) {
17474 S.Diag(E->getExprLoc(), diag::err_unknown_any_function)
17475 << VD << E->getSourceRange();
17476 return ExprError();
17477 }
17478 if (const FunctionProtoType *FT = Type->getAs<FunctionProtoType>()) {
17479 // We must match the FunctionDecl's type to the hack introduced in
17480 // RebuildUnknownAnyExpr::VisitCallExpr to vararg functions of unknown
17481 // type. See the lengthy commentary in that routine.
17482 QualType FDT = FD->getType();
17483 const FunctionType *FnType = FDT->castAs<FunctionType>();
17484 const FunctionProtoType *Proto = dyn_cast_or_null<FunctionProtoType>(FnType);
17485 DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
17486 if (DRE && Proto && Proto->getParamTypes().empty() && Proto->isVariadic()) {
17487 SourceLocation Loc = FD->getLocation();
17488 FunctionDecl *NewFD = FunctionDecl::Create(S.Context,
17489 FD->getDeclContext(),
17490 Loc, Loc, FD->getNameInfo().getName(),
17491 DestType, FD->getTypeSourceInfo(),
17492 SC_None, false/*isInlineSpecified*/,
17493 FD->hasPrototype(),
17494 false/*isConstexprSpecified*/);
17495
17496 if (FD->getQualifier())
17497 NewFD->setQualifierInfo(FD->getQualifierLoc());
17498
17499 SmallVector<ParmVarDecl*, 16> Params;
17500 for (const auto &AI : FT->param_types()) {
17501 ParmVarDecl *Param =
17502 S.BuildParmVarDeclForTypedef(FD, Loc, AI);
17503 Param->setScopeInfo(0, Params.size());
17504 Params.push_back(Param);
17505 }
17506 NewFD->setParams(Params);
17507 DRE->setDecl(NewFD);
17508 VD = DRE->getDecl();
17509 }
17510 }
17511
17512 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
17513 if (MD->isInstance()) {
17514 ValueKind = VK_RValue;
17515 Type = S.Context.BoundMemberTy;
17516 }
17517
17518 // Function references aren't l-values in C.
17519 if (!S.getLangOpts().CPlusPlus)
17520 ValueKind = VK_RValue;
17521
17522 // - variables
17523 } else if (isa<VarDecl>(VD)) {
17524 if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) {
17525 Type = RefTy->getPointeeType();
17526 } else if (Type->isFunctionType()) {
17527 S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type)
17528 << VD << E->getSourceRange();
17529 return ExprError();
17530 }
17531
17532 // - nothing else
17533 } else {
17534 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl)
17535 << VD << E->getSourceRange();
17536 return ExprError();
17537 }
17538
17539 // Modifying the declaration like this is friendly to IR-gen but
17540 // also really dangerous.
17541 VD->setType(DestType);
17542 E->setType(Type);
17543 E->setValueKind(ValueKind);
17544 return E;
17545}
17546
17547/// Check a cast of an unknown-any type. We intentionally only
17548/// trigger this for C-style casts.
17549ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
17550 Expr *CastExpr, CastKind &CastKind,
17551 ExprValueKind &VK, CXXCastPath &Path) {
17552 // The type we're casting to must be either void or complete.
17553 if (!CastType->isVoidType() &&
17554 RequireCompleteType(TypeRange.getBegin(), CastType,
17555 diag::err_typecheck_cast_to_incomplete))
17556 return ExprError();
17557
17558 // Rewrite the casted expression from scratch.
17559 ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr);
17560 if (!result.isUsable()) return ExprError();
17561
17562 CastExpr = result.get();
17563 VK = CastExpr->getValueKind();
17564 CastKind = CK_NoOp;
17565
17566 return CastExpr;
17567}
17568
17569ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) {
17570 return RebuildUnknownAnyExpr(*this, ToType).Visit(E);
17571}
17572
17573ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc,
17574 Expr *arg, QualType &paramType) {
17575 // If the syntactic form of the argument is not an explicit cast of
17576 // any sort, just do default argument promotion.
17577 ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(arg->IgnoreParens());
17578 if (!castArg) {
17579 ExprResult result = DefaultArgumentPromotion(arg);
17580 if (result.isInvalid()) return ExprError();
17581 paramType = result.get()->getType();
17582 return result;
17583 }
17584
17585 // Otherwise, use the type that was written in the explicit cast.
17586 assert(!arg->hasPlaceholderType());
17587 paramType = castArg->getTypeAsWritten();
17588
17589 // Copy-initialize a parameter of that type.
17590 InitializedEntity entity =
17591 InitializedEntity::InitializeParameter(Context, paramType,
17592 /*consumed*/ false);
17593 return PerformCopyInitialization(entity, callLoc, arg);
17594}
17595
17596static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) {
17597 Expr *orig = E;
17598 unsigned diagID = diag::err_uncasted_use_of_unknown_any;
17599 while (true) {
17600 E = E->IgnoreParenImpCasts();
17601 if (CallExpr *call = dyn_cast<CallExpr>(E)) {
17602 E = call->getCallee();
17603 diagID = diag::err_uncasted_call_of_unknown_any;
17604 } else {
17605 break;
17606 }
17607 }
17608
17609 SourceLocation loc;
17610 NamedDecl *d;
17611 if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) {
17612 loc = ref->getLocation();
17613 d = ref->getDecl();
17614 } else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) {
17615 loc = mem->getMemberLoc();
17616 d = mem->getMemberDecl();
17617 } else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) {
17618 diagID = diag::err_uncasted_call_of_unknown_any;
17619 loc = msg->getSelectorStartLoc();
17620 d = msg->getMethodDecl();
17621 if (!d) {
17622 S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method)
17623 << static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector()
17624 << orig->getSourceRange();
17625 return ExprError();
17626 }
17627 } else {
17628 S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
17629 << E->getSourceRange();
17630 return ExprError();
17631 }
17632
17633 S.Diag(loc, diagID) << d << orig->getSourceRange();
17634
17635 // Never recoverable.
17636 return ExprError();
17637}
17638
17639/// Check for operands with placeholder types and complain if found.
17640/// Returns ExprError() if there was an error and no recovery was possible.
17641ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
17642 if (!getLangOpts().CPlusPlus) {
17643 // C cannot handle TypoExpr nodes on either side of a binop because it
17644 // doesn't handle dependent types properly, so make sure any TypoExprs have
17645 // been dealt with before checking the operands.
17646 ExprResult Result = CorrectDelayedTyposInExpr(E);
17647 if (!Result.isUsable()) return ExprError();
17648 E = Result.get();
17649 }
17650
17651 const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType();
17652 if (!placeholderType) return E;
17653
17654 switch (placeholderType->getKind()) {
17655
17656 // Overloaded expressions.
17657 case BuiltinType::Overload: {
17658 // Try to resolve a single function template specialization.
17659 // This is obligatory.
17660 ExprResult Result = E;
17661 if (ResolveAndFixSingleFunctionTemplateSpecialization(Result, false))
17662 return Result;
17663
17664 // No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
17665 // leaves Result unchanged on failure.
17666 Result = E;
17667 if (resolveAndFixAddressOfOnlyViableOverloadCandidate(Result))
17668 return Result;
17669
17670 // If that failed, try to recover with a call.
17671 tryToRecoverWithCall(Result, PDiag(diag::err_ovl_unresolvable),
17672 /*complain*/ true);
17673 return Result;
17674 }
17675
17676 // Bound member functions.
17677 case BuiltinType::BoundMember: {
17678 ExprResult result = E;
17679 const Expr *BME = E->IgnoreParens();
17680 PartialDiagnostic PD = PDiag(diag::err_bound_member_function);
17681 // Try to give a nicer diagnostic if it is a bound member that we recognize.
17682 if (isa<CXXPseudoDestructorExpr>(BME)) {
17683 PD = PDiag(diag::err_dtor_expr_without_call) << /*pseudo-destructor*/ 1;
17684 } else if (const auto *ME = dyn_cast<MemberExpr>(BME)) {
17685 if (ME->getMemberNameInfo().getName().getNameKind() ==
17686 DeclarationName::CXXDestructorName)
17687 PD = PDiag(diag::err_dtor_expr_without_call) << /*destructor*/ 0;
17688 }
17689 tryToRecoverWithCall(result, PD,
17690 /*complain*/ true);
17691 return result;
17692 }
17693
17694 // ARC unbridged casts.
17695 case BuiltinType::ARCUnbridgedCast: {
17696 Expr *realCast = stripARCUnbridgedCast(E);
17697 diagnoseARCUnbridgedCast(realCast);
17698 return realCast;
17699 }
17700
17701 // Expressions of unknown type.
17702 case BuiltinType::UnknownAny:
17703 return diagnoseUnknownAnyExpr(*this, E);
17704
17705 // Pseudo-objects.
17706 case BuiltinType::PseudoObject:
17707 return checkPseudoObjectRValue(E);
17708
17709 case BuiltinType::BuiltinFn: {
17710 // Accept __noop without parens by implicitly converting it to a call expr.
17711 auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
17712 if (DRE) {
17713 auto *FD = cast<FunctionDecl>(DRE->getDecl());
17714 if (FD->getBuiltinID() == Builtin::BI__noop) {
17715 E = ImpCastExprToType(E, Context.getPointerType(FD->getType()),
17716 CK_BuiltinFnToFnPtr)
17717 .get();
17718 return CallExpr::Create(Context, E, /*Args=*/{}, Context.IntTy,
17719 VK_RValue, SourceLocation());
17720 }
17721 }
17722
17723 Diag(E->getBeginLoc(), diag::err_builtin_fn_use);
17724 return ExprError();
17725 }
17726
17727 // Expressions of unknown type.
17728 case BuiltinType::OMPArraySection:
17729 Diag(E->getBeginLoc(), diag::err_omp_array_section_use);
17730 return ExprError();
17731
17732 // Everything else should be impossible.
17733#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
17734 case BuiltinType::Id:
17735#include "clang/Basic/OpenCLImageTypes.def"
17736#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
17737 case BuiltinType::Id:
17738#include "clang/Basic/OpenCLExtensionTypes.def"
17739#define BUILTIN_TYPE(Id, SingletonId) case BuiltinType::Id:
17740#define PLACEHOLDER_TYPE(Id, SingletonId)
17741#include "clang/AST/BuiltinTypes.def"
17742 break;
17743 }
17744
17745 llvm_unreachable("invalid placeholder type!");
17746}
17747
17748bool Sema::CheckCaseExpression(Expr *E) {
17749 if (E->isTypeDependent())
17750 return true;
17751 if (E->isValueDependent() || E->isIntegerConstantExpr(Context))
17752 return E->getType()->isIntegralOrEnumerationType();
17753 return false;
17754}
17755
17756/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
17757ExprResult
17758Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
17759 assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) &&
17760 "Unknown Objective-C Boolean value!");
17761 QualType BoolT = Context.ObjCBuiltinBoolTy;
17762 if (!Context.getBOOLDecl()) {
17763 LookupResult Result(*this, &Context.Idents.get("BOOL"), OpLoc,
17764 Sema::LookupOrdinaryName);
17765 if (LookupName(Result, getCurScope()) && Result.isSingleResult()) {
17766 NamedDecl *ND = Result.getFoundDecl();
17767 if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
17768 Context.setBOOLDecl(TD);
17769 }
17770 }
17771 if (Context.getBOOLDecl())
17772 BoolT = Context.getBOOLType();
17773 return new (Context)
17774 ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, BoolT, OpLoc);
17775}
17776
17777ExprResult Sema::ActOnObjCAvailabilityCheckExpr(
17778 llvm::ArrayRef<AvailabilitySpec> AvailSpecs, SourceLocation AtLoc,
17779 SourceLocation RParen) {
17780
17781 StringRef Platform = getASTContext().getTargetInfo().getPlatformName();
17782
17783 auto Spec = llvm::find_if(AvailSpecs, [&](const AvailabilitySpec &Spec) {
17784 return Spec.getPlatform() == Platform;
17785 });
17786
17787 VersionTuple Version;
17788 if (Spec != AvailSpecs.end())
17789 Version = Spec->getVersion();
17790
17791 // The use of `@available` in the enclosing function should be analyzed to
17792 // warn when it's used inappropriately (i.e. not if(@available)).
17793 if (getCurFunctionOrMethodDecl())
17794 getEnclosingFunction()->HasPotentialAvailabilityViolations = true;
17795 else if (getCurBlock() || getCurLambda())
17796 getCurFunction()->HasPotentialAvailabilityViolations = true;
17797
17798 return new (Context)
17799 ObjCAvailabilityCheckExpr(Version, AtLoc, RParen, Context.BoolTy);
17800}
17801